Polydiorganosiloxane oligourea segmented copolymers and a process for making same

ABSTRACT

The present invention provides polydiorganosiloxane oligourea segmented copolymers. The copolymers contain soft polydiorganosiloxane units, hard segments that are diisocyanate residues, the polydiorganosiloxane units and diisocyanate residues being connected by urea linkages, and terminal groups that are non-reactive, reactive under free radical or moisture cure conditions, or amines. The invention also provides methods of preparing the copolymers.

FIELD OF THE INVENTION

This invention relates to polydiorganosiloxane oligourea segmentedcopolymers and a process for making same.

BACKGROUND OF THE INVENTION

Polydiorganosiloxane polymers have unique properties derived mainly fromthe physical and chemical characteristics of the siloxane bond.Typically, the outstanding properties of polydiorganosiloxane polymersinclude resistance to ultraviolet light, extremely low glass transitiontemperature, good thermal and oxidative stability, good permeability tomany gases, very low surface energy, low index of refraction, goodhydrophobicity, and good dielectric properties. They also have very goodbiocompatability and are of great interest as biomaterials that can beused in the body in the presence of blood. Polydiorganosiloxaneelastomers have been widely used because of these many excellentproperties. But, their limited tear resistance and poor resistance tolow polarity solvents have made them unsuitable in many otherapplications.

Elastomers possess the ability to recover their initial shape fromdeformation produced by an imposed force. Traditionalpolydiorganosiloxanes show elastomeric behavior only when they arechemically or physically crosslinked. Even extremely high molecularweight polydiorganosiloxane gums (greater than 500,000 grams per mole)exhibit cold flow when uncrosslinked. However, chemical crosslinkingresults in polymers with poor mechanical properties relative to otherorganic materials. Thus, to be useful in most commercial applications,traditional polydiorganosiloxanes must be further filled with up to 50weight percent fillers such as finely divided high surface area silica,fumed silica, titanium dioxide, alumina, zirconia, pigment-grade oxides,carbon blacks, graphite, metal powders, clays, calcium carbonates,silicates, aluminates, fibrous fillers, and hollow glass or plasticmicrospheres, depending on the desired properties, for example, tomaintain their mechanical strength and reduce swelling in solvents.Since polydiorganosiloxanes do not lose their mechanical strength asabruptly as other organic materials at elevated temperatures, they findparticular use in high temperature applications.

For many uses such as in insulated wire, rods, channels, tubing, andsimilar products, polydiorganosiloxane compounds are extruded instandard rubber extrusion equipment. The extruded material mustimmediately be heated to set the form. Usually, hot-air vulcanization at300-450° C. or steam at 0.28-0.70 MPa (40-100 psi) for several minutesis needed. Final properties can be developed by oven curing or bycontinuous steam vulcanization.

For many other uses such as in elastomers, caulking, gaskets, sealants,and release coatings, polydiorganosiloxane compounds are applied asliquids or deformable semi-solids at room temperature and requireintimate mixing if two part systems are used. Final properties aredeveloped after lengthy cure times and are generally inferior. Often adelay occurs before the next sequence in manufacture or repair canproceed.

In recent years, free radically cured and moisture cured liquidpolydiorganosiloxane compositions have been disclosed that cure rapidlyand completely under exposure to radiation or moderately elevatedtemperatures with excellent properties. Thus, subsequent manufacturingor repair steps are often delayed until some degree of curing occurs.Also, thick constructions cannot be made without temporary support untilcuring is accomplished and irregularly shaped surfaces can be difficultto coat adequately. Therefore, there is still a need forpolydiorganosiloxane compositions with green strength, i.e., strength inthe uncured state, and controlled flow properties.

Silicone-based release coatings have been used commercially for sometime, predominantly in such applications as release liners foradhesives. Generally, these materials are coated from solvent or acarrier and thermally crosslinked at high temperatures. Recently,silicone release technologies have been disclosed that include additioncure, cationic cure, radiation cure, and moisture cure of monomer,oligomer or polymer systems as well as silicone-containing blockcopolymers that do not require curing. Some of these systems can becoated without solvent, e.g., by roll coating. Others can be coated fromorganic solvents or water. There is still a need for a silicone-basedcoating with controlled flow properties and good green strength whileretaining the desirable release performance features of the previouslymentioned materials.

Physically crosslinked polydiorganosiloxane polyurea segmentedcopolymers, that may contain blocks other than polydiorganosiloxane orurea, are elastomers that are synthesized in and coated out of solvent.These copolymers have some potential process economy advantages becausetheir synthesis reaction is rapid, requires no catalyst, and produces noby-products.

In producing polydiorganosiloxane polyurea segmented copolymers,monofunctional reaction impurities in the polydiorganosiloxane diamineprecursor can inhibit the chain extension reaction and limit theattainment of optimum molecular weight and tensile strength of thepolymer. Because the early processes for making the polydiorganosiloxanediamines resulted in increasing levels of monofunctional impurities withincreasing molecular weight, it was not possible to achieve elastomershaving satisfactory mechanical properties for most elastomer or adhesiveapplications. More recently, processes have been developed that producelow levels of impurities over a wide range of polydiorganosiloxanediamine molecular weights. With these processes polydiorganosiloxanepolyurea segmented copolymers have been obtained that have goodmechanical properties through the use of chain extenders to increase thenon-silicone content. However, these systems, with or without chainextender, do not flow at room temperature.

Continuous melt polymerization processes have been used to producepolyurethane elastomers and acrylate pressure-sensitive adhesives.Polyetherimides, which can contain polydiorganosiloxane segments, havealso been produced in a continuous melt polymerization process. Recentlypolyurethane resins have been described that use polydiorganosiloxaneurea segments to prevent blocking of films formed from the resin.However, levels of reactive polydiorganosiloxane in the compositionswere small, for example, less than 15 weight percent, and incompleteincorporation of the polydiorganosiloxane into the backbone was notdetrimental since easy release was the intent. Unincorporatedpolydiorganosiloxane oil can, however, act as a plasticizing agent inelastomers to reduce tensile strength or detackify and reduce shearproperties of pressure-sensitive adhesives. This unincorporated oil canalso bloom to the surface of an elastomer or adhesive and contaminateother surfaces with which it is in contact.

SUMMARY OF THE INVENTION

Briefly, in one aspect of the present invention, polydiorganosiloxaneoligourea segmented copolymers are provided wherein such copolymerscomprise soft polydiorganosiloxane diamine units, hard polyisocyanateresidue units, wherein the polyisocyanate residue is the polyisocyanateminus the —NCO groups, optionally, soft and/or hard organic polyamineunits, wherein residues of the isocyanates amine units are connected byurea linkages, and terminal groups, wherein the terminals groups arenon-functional endcapping groups or functional endcapping groups.

The present invention further provides polydiorganosiloxane oligoureasegmented copolymer compositions comprising the reaction product of

(a) at least one polyisocyanate;

(b) an endcapping agent having a terminal selected frompolydiorganosiloxane monoamines and non-siloxane containing endcappingagents having a terminal portion reactive with an amine or isocyanateand a terminal portion that is non-functional or that can react undermoisture-cure or free-radical conditions,

with the provisos (1) that if no polydiorganosiloxane monoamine ispresent, then at least one polyamine is present, wherein polyaminecomprises at least one polydiorganosiloxane diamine or a mixture of atleast one polydiorganosiloxane diamine and at least one organicpolyamine, (2) if only polyisocyanate and polyamine are present, themolar ratio of isocyanate to amine is <0.9:1 or >1.1:1, and (3) whenpolydiorganosiloxane monoamine and diamine are present, the ratio oftotal isocyanate available in the polyisocyanate to the total amineavailable in the monoamine and diamine less any amine end groups in thecopolymer is about 1:1.

The polydiorganosiloxane oligourea segmented copolymer compositions ofthe present invention can be represented by Formula I. Anyoneknowledgeable in the art would know that the oligomerization processleads to randomization of the polydiorganosiloxane diamine and organicpolyamines along the back one. This could lead to the organic polyaminereacting with the endcapper.

wherein

each Z is a polyvalent radical selected from arylene radicals andaralkylene radicals preferably having from about 6 to 20 carbon atoms,alkylene and cycloalkylene radicals preferably having from about 6 to 20carbon atoms, preferably Z is 2,6-tolylene, 4,4′-melthylenediphenylene,3,3′-dimethoxy-4,4′-biphenylene, tetramethyl-m-xylylene,4,4′-methylenedicyclohexylene, 3,5,5-trimethyl-3-methylenecyclohexylene,2,2,4-trimethylhexylene, 1,6-hexamethylene, 1,4-cyclohexylene, andmixtures thereof;

each R is a moiety independently selected from alkyl moieties preferablyhaving about 1 to 12 carbon atoms and may be substituted with, forexample, trifluoroalkyl or vinyl groups, a vinyl radical or higheralkenyl radical preferably represented by the formula —R²(CH₂)_(a)CH═CH₂wherein R² is —(CH₂)_(b)— or —(CH₂)_(c)CH═CH— and a is 1, 2 or 3, b is0, 3 or 6; and c is 3, 4 or 5; a cycloalkyl moiety having about 6 to 12carbon atoms and may be substituted with alkyl, fluoroalkyl, and vinylgroups, or an aryl moiety preferably having about 6 to 20 carbon atomsand that may be substituted with, for example, alkyl, cycloalkyl,fluoroalkyl and vinyl groups or R is a perfluoroalkyl group as describedin U.S. Pat. No. 5,028,679, wherein such description is incorporatedherein by reference, a fluorine-containing group as described in U.S.Pat. No. 5,236,997, wherein such description is incorporated herein byreference or a perfluoroether-containing group, as described in U.S.Pat. Nos. 4,900,474 and 5,118,775, wherein such descriptions areincorporated herein by reference, preferably at least 50% of the Rmoieties are methyl radicals with the balance being monovalent alkyl orsubstituted alkyl radicals having 1 to 12 carbon atoms, vinyleneradicals, phenyl radicals, or substituted phenyl radicals;

each Y is a polyvalent moiety independently selected from an alkyleneradical preferably having 1 to 10 carbon atoms, aralkylene radical andarylene radical, preferably having 6 to 20 carbon atoms;

each D is independently selected from hydrogen, alkyl radicalspreferably having 1 to 10 carbon atoms, phenyl, and a radical thatcompletes a ring structure including B or Y to form a heterocycle,preferably having about 6 to 20 carbon atoms;

each A is independently —B—, or —YSi(R)₂(OSi(R)₂)_(p)Y— or mixturesthereof;

B is a polyvalent radical selected from the group consisting ofalkylene, aralkylene, cycloalkylene, phenylene, polyalkylene oxide, suchas, polyethylene oxide, polypropylene oxide, polytetramethylene oxide,and copolymers thereof, and mixtures thereof;

m is a number that is 0 to about 8;

b, e, d and n are 0 or 1, with the provisos that, b+d=1 and e+n=1;

p is about 10 or larger, preferably about 15 to 2000, more preferablyabout 30 to 1500;

q is about 10 or larger, preferably about 15 to 2000, more preferablyabout 30 to 1500; and

t is a number which is 0 to about 8;

s is 0 or 1; and

each X is independently:

(a) a moiety represented by

wherein D is defined as above;

(b) a moiety represented by

where each of D, and Z are defined as above,

(c) a monovalent moiety that is not reactive under moisture curing orfree radical curing conditions and that can be the same or different andthat are alkyl moieties preferably having about 1 to 20 carbon atoms andthat can be substituted with, for example, trifluoroalkyl groups, oraryl moieties preferably having about 6 to 20 carbon atoms and that maybe substituted with, for example alkyl, aryl, and substituted arylgroups and a particularly useful embodiment when X is C, is when t=0 andm=0;

(d) a moiety represented by

where each of Z, and D are defined as above,

K is independently (i) a moiety that is not reactive under moisturecuring or free radical curing conditions and that can be the same ordifferent selected from the group consisting of alkyl, substitutedalkyl, aryl, and substituted aryl; (ii) a free radically curable endgroup such as, for example acrylate, methacrylate, acrylamido,methacrylamido and vinyl groups; (iii) a moisture curable group such as,for example, alkoxysilane and oxime silane groups, and

(e) a moiety represented by

wherein D, Y and K are defined as above.

In the use of polyisocyanates (Z is a radical having a functionalitygreater than 2) and polyamines (B is a radical having a functionalitygreater than 2), the structure of Formula I will be modified to reflectbranching at the polymer backbone.

The average degree of oligomerization refers to the size of theresultant oligomer molecule and is determined from the number average ofthe residue of amine-containing reactant molecules in the oligomer.There are two ways of obtaining the desired degree of oligomerization:(1) control the isocyanate to amine ratio to obtain either isocyanate oramine endcapped oligomer (X=a or b), and (2) judiciously select theamount of monoamine or monoisocyanate endcapper with stoichiometricamounts of isocyanate and amine (X=c, d, or e). The following tabledisplays the mol ratios of the various molecules necessary for buildinga molecule with the desired endcapper X. For the use of polyamines andpolyisocyanates, the ratios may be adjusted accordingly.

X(a) X(b) X(c) X(d) X(e) Degree of t + m + 2 t + m + 2 t + m + 2 t + m +4 t + m + 2 oligomeri- zation Polydi- t + m + 2 t + m + 2 t + m + 2 t +m + 2 t + m + 2 organo- siloxane diamine Diisocyanate t + m + 1 t + m +3 t + m + 1 t + m + 3 t + m + 1 Polydi- — — 2 — — organo- siloxanemonoamine Organic — — — 2 — monoamine Monoiso- — — — — 2 cyanate

The polydiorganosiloxane oligourea segmented copolymers of the presentinvention can be prepared to exhibit desired controlled flow propertiesin the uncured state, being liquid or semi-solid at ambienttemperatures. The controlled flow properties of the copolymer can beoptimized by appropriate selection of the polyisocyanate, the molecularweight of the polydiorganosiloxane amine, the average degree ofoligomerization, the organic polyamine selected, and the nature of Z.Generally, the green strength of the resultant polydiorganosiloxanepolyurea segmented oligomer increases with decreasingpolydiorganosiloxane amine molecular weight. The compositions of thepresent invention have an average degree of oligomerization of between 2and 12.

The polydiorganosiloxane oligourea segmented copolymers of the presentinvention have diverse utility. The copolymers possess the conventionalexcellent physical properties associated with polysiloxanes of low glasstransition temperature, high thermal and oxidative stabilities, UVresistance, low surface energy and hydrophobicity, good electricalproperties and high permeability to many gases.

When the polydiorganosiloxane oligourea segmented copolymers areterminated with non-functional end groups, the resulting copolymerspossess the thermally reversible properties of a gel, semisolid, orsolid at room temperature and of a fluid at elevated temperatures.Selected polydiorganosiloxane oligourea segmented copolymers of thepresent invention have a surprisingly low melt flow viscosity and abruptsolidification at a temperature below the melt flow conditions.Additionally, these selected copolymers exhibit ease of reprocessingwithout additional stabilizers that make them suitable as thermallyreversible encapsulants and potting compounds or as caulking compoundswhere sharp or reversible liquid/solid transitions are desired, forexample, such as in assembly line operations.

Advantageously, the selection of the terminal group used to prepare thecopolymers of the present invention can provide a variety of materialshaving various properties. The terminal groups of the copolymer caneither be non-functional or functional. If the terminal group is afunctional end-capping group, the resultant copolymers have a latentreactivity, such that these functional end-capped copolymers can serveas prepolymer units, can be crosslinked, can be cured, and the like.

When the polydiorganosiloxane oligourea segmented copolymers of thepresent invention are terminated with reactive amine end groups, theycan be further reacted with multifunctional isocyanates, multifunctionalacrylates, multifunctional anhydrides, or mixtures thereof to obtainvarious crosslinked branched, or chain-extended materials.

When the polydiorganosiloxane oligourea segmented copolymers of thepresent invention are terminated wvitlh reactive isocyanate end groups,they can be further reacted with water, multifunctional amines,multifunctional alcohols, multifunctional mercaptans, or mixturesthereof to obtain various crosslinked branched, or chain-extendedmaterials.

Additionally, when the polydiorganosiloxane oligourea segmentedcopolymers of the invention are terminated with a chemically curable endgroup, the resulting green strength, that is, strength prior to curing,is generally greater than that for chemically crosslinkable siliconecompositions known in the art.

The polydiorganosiloxane oligourea segmented copolymers of the presentinvention having free radically curable end groups can be solutioncoated or hot melt coated easily without placirg adverse stresses intothe coating and can be formed into irregular shapes that will hold theirshape until they are thermally or radiation cured. Such a feature makesthem useful, for example, in applications such as gaskets, sealants, andreplicated surfaces and coatings on easily deformable substrates.

The polydiorganosiloxane oligourea segmented copolymers of the presentinvention having moisture curable end groups can be solution coated orhot melt coated in a manner similar to the free radically cured forms,or applied to a variety of irregular substrates in situations that donot allow subsequent thermal or radiation curing treatments or in whichfree radical reactions are inhibited by the presence of oxygen. Suchcharacteristics make them useful, for example, in applications in thebuilding construction industry, such as caulking and sealants, and inareas where oxygen inhibited radiation or thermal treatments are notpreferred.

The polydiorganosiloxane oligourea segmented copolymers of the presentinvention with both free radically curable end groups and moisturecurable end groups are useful, for example, in situations where partialcure by one mechanism is desirable followed by complete cure by anothermethod. Areas where this feature is useful include situations where asubsequent manufacturing operation is desired and superior greenstrength is beneficial, such as in assembly line operations.

The present invention further provides a solvent process and asolventless process for producing the polydiorganosiloxane oligoureasegmented copolymers of the present invention.

The solvent process comprises the steps of

providing reactants, wherein the reactants comprise (a) apolyisocyanate; (b) an endcapping agent selected frompolydiorganosiloxane monoamines and non-siloxane containing endcappingagents having a terminal portion reactive with an amine or isocyanateand a terminal portion that is non-functional or that can react undermoisture-cure or free-radical conditions; with the provisos (1) that ifno polydiorganosiloxane monoamine is present, then at least onepolyamine is present, wherein polyamine comprises at least onepolydiorganosiloxane diamine or mixtures of at least onepolydiorganosilxane diamine and at least one organic polyamine, (2) ifonly polyisocyanate and polyamine are present, the molar ratio ofisocyanate to amine is <0.9:1 or >1.1:1, and (3) whenpolydiorganosiloxane monoamine and diamine are present, the ratio oftotal isocyanate available in the polyisocyanate to the total amineavailable in the monoamine and diamine less any amine end groups in thecopolymer is about 1:1; and (c) solvent to a reactor;

mixing the reactants in the reactor;

allowing the reactants to react to form a polydiorganosiloxane oligoureasegmented copolymer with an average degree of oligomerization of 2 to12; and

conveying the oligomer from the reactor.

The solventless process comprises the steps of:

continuously providing (a) a polyisocyanate; (b) an endcapping agentselected from polydiorganosiloxane monoamines and non-siloxanecontaining endcapping agents having a terminal portion reactive with anamine or isocyanate and a terminal portion that is non-functional orthat can react under moisture-cure or free-radical conditions;

with the provisos (1) that if no polydiorganosiloxane monoamine ispresent, then at least one polyamine is present, wherein polyaminecomprises at least one polydiorganosiloxane diamine or a mixture of atleast one polydiorganosiloxane diamine and at least one organicpolyamine, (2) if only polyisocyanate and polyamine are present, themolar ratio of isocyanate to amine is <0.9:1 or >1.1:1, and (3) whenpolydiorganosiloxane monoamine and diamine are present, the ratio oftotal isocyanate available in the polyisocyanate to the total amineavailable in the monoamine and diamine less any amine end groups in thecopolymer is about 1:1, to a reactor under substantially solventlessconditions;

mixing the reactants in the reactor under the substantially solventlessconditions;

allowing the reactants to react to form a polydiorganosiloxane oligoureasegmented copolymer with a average degree of oligomerization of 2 to 12;and

conveying the oligomer from the reactor.

In the solventless process, generally, no solvent is needed to carry outthe reaction, making the process more environmentally friendly than thesolvent process for making polydiorganosiloxane oligourea segmentedcopolymers. Small amounts of solvent may be present, if necessary, tocontrol the flow of solid polyisocyanates, high viscositypolyisocyanates, low amounts of polyisocyanates, or for controlledaddition of adjuvants such as tackifying resins, pigments, crosslinkingagents, plasticizers, fillers, and stabilizing agents, or to reducetheir viscosity. An additional benefit of the continuous, solventlessprocess of the present invention is the ability to extrude thepolydiorganosiloxane polyurea segmented oligomer into thickconstructions, into patterned shapes or onto irregularly-shaped surfacesdirectly after polymerization.

DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

Different polyisocyanates in the reaction will modify the properties ofthe polydiorganosiloxane oligourea segmented copolymer. For example, ifa polycarbodiimide-modified diphenylmethane diisocyanate, such asISONATE™ 143L, available from Dow Chemical Co., is used, the resultingpolydiorganosiloxane oligourea segmented copolymer has superior solventresistance when compared with other polyisocyanates. Iftetramethyl-m-xylylene diisocyanate is used, the resulting segmentedcopolymer may be a semisolid to solid gel that has a very low meltviscosity that makes it particularly useful in potting and sealantapplications where thermal reversibility is advantageous.

Any diisocyanate that can be represented by the formula

OCN—Z—NCO

wherein Z is as defined above, can be used in the present invention.Examples of such diisocyanates include, but are not limited to, aromaticdiisocyanates, such as 2,6-toluene diisocyanate, 2,5-toluenediisocyanate, 2,4-toluene diisocyanate, m-phenylene diisocyanate,p-phenylene diisocyanate, methylene bis(o-chlorophenyl diisocyanate),methylenediphenylene-4,4′-diisocyanate, polycarbodiimide-modifiedmethylenediphenylene diisocyanate, (4,4′-diisocyanato-3,3′, 5,5′-tetraethyl) biphenylmethane, 4,4′-diisocyanato-3,3′-dimethoxybiphenyl(o-dianisidine diisocyanate), 5-chloro-2,4-toluene diisocyanate,1-chloromethyl-2,4-diisocyanato benzene, aromatic-aliphaticdiisocyanates such as m-xylylene diisocyanate, tetramethyl-m-xylylenediisocyanate, aliphatic diisocyanates, such as 1,4-diisocyanatobutane,1,6-diisocyanatohexane, 2,2,4-trimethylhexyl diisocyanate,1,12-diisocyanatododecane, 2-methyl-1,5-diisocyanatopentane, andcycloaliphatic diisocyanates such asmethylene-dicyclohexylene-4,4′-diisocyanate, and3-isocyanatomethyl-3,5,5-trimethyl-cyclohexyl isocyanate and mixturesthereof.

Preferred diisocyanates include 2,6-toluene diisocyanate,methylenediphenylene-4,4′-diisocyanate, polycarbodiimide-modifiedmethylenediphenyl diisocyanate, o-dianisidine diisocyanate,tetramethyl-m-xylylene diisocyanate,methylenedicyclohexylene-4,4′-diisocyanate,3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (isophoronediisocyanate), 2,2,4-trimethylhexyl diisocyanate,1,6-diisocyanatohexane, and cyclohexylene-1,4-diisocyanate. Particularlypreferred is tetramethyl-m-xylylene diisocyanate and mixtures thereof.

Any triisocyanate that can react with a monoamine and polyamine can beused in the present invention. Examples of such triisocyanates include,but are not limited to, polyfunctional isocyanates, such as thoseproduced from biurets, isocyanurates, adducts, and the like, may beused. Some commercially available polyisocyanates include portions ofthe DESMODUR™ and MONDUR™ series from Bayer and the PAPI series of DowPlastics.

Preferred triisocyanates include DESMODUR™ N-3300 and MONDUR™ 489.

Terminal Groups

Polydiorganosiloxane monoamines useful in the present invention as endcapping agents can be represented by the formula

where D, R, X(c), Y and q are as described above, and include thosehaving number average molecular weights in the range of about 700 to150,000. Preferred are polydiorganosiloxane monoamines prepared asdeescribed in U.S. Pat. No. 5,091,483, wherein such description isincorporated herein by reference. The polydiorganosiloxane monoaminescan be prepared, for example, from the reaction of cyclicorganotrisiloxanes with alkyl lithium reagents in tetrahydrofuran toyield lithium polydiorganosiloxanolates that are subsequently reactedwith aminoalkylfluorosilanes as terminating agents to provide thepolydiorganosiloxane monoamine product.

Examples of siloxane monoamines useful in the present invention includepolydimethylsiloxane monoamine, polydiphenylsiloxane monoamine,polytrifluoropropylmethylsiloxane monoamine, polyphenylmethylsiloxanemonoamine, polydiethylsiloxane monoamine, polydivinylsiloxane monoamine,polyvinylmethylsiloxane monoamine, and copolymers thereof and mixturesthereof.

Suitable endcapping agents for polydiorganosiloxane oligourea segmentedcopolymers that would be terminated with amine groups, were noendcapping agent present, and that provide terminal groups that are notreactive under moisture curing or free radical curing conditions includebut are not limited to monoisocyanates such as alkyl isocyanates, suchas benzyl isocyanate, cyclohexyl isocyanate, n-dodecyl isocyanate,n-octadecyl isocyanate, octyl isocyanate, 2-phenylethyl isocyanate,trimethylsilyl isocyanate, undecyl isocyanate; and aryl isocyanates,such as 4-bromophenyl isocyanate, 2-chlorophenyl isocyanate,2,4-dimethylphenyl isocyanate, 1-naphthyl isocyanate, phenyl isocyanate,4-tolyl isocyanate, 4-trifluoromethylphenyl isocyanate,2,4,6-trimethylphenyl isocyanate.

Suitable endcapping agents for polydiorganosiloxane oligourea segmentedcopolymers that would be terminated with isocyanate groups, were noendcapping agent present, and provide terminal groups that are notreactive under moisture curing or free radical curing conditions includebut are not limited to organic monoamines such as propylamine,cyclohexylamine, aniline, benzylamine, octadecylamine, phenylethylamine,and polyoxyalkylene monoamine, such as those that can be obtained fromHuntsman, Corp. under the tradename of Jeffamine, polyethylene oxide,polypropylene oxide, copolymers thereof and mixtures thereof.

Suitable endcapping agents for polydiorganosiloxane oligourea segmentedcopolymers that would be terminated with amine groups, were noendcapping agent present, and that provide terminal groups that arereactive under free radical curing conditions, include but are notlimited to isocyanatoethyl methacrylate; alkenyl azlactones such asvinyl dimethyl azlactone and isopropenyl dimethyl azlactone,m-isopropenyl-α,α-dimethyl benzyl isocyanate, and acryloyl ethylcarbonic anhydride. Some endcapping agents that can react with aminegroups, e.g., isocyanatoethyl methacrylate, are commercially available,and others can be prepared using known methods. Alkenyl azlactones andtheir preparations are described, for example, in U.S. Pat. No.4,777,276, wherein such description is incorporated herein by reference.Acryloyl ethyl carbonic anhydride can be prepared from ethylchloroformate and acrylic acid as described in R. Hatada et al., Bull.Chem. Soc, Japan, 41 (10), 2521 (1968). Preferred endcapping agents forpolydiorganosiloxane oligourea segmented copolymers that would be amineterminated if no endcapping agent were present include, for example,isocyanatoethyl methacrylate, vinyl dimethyl azlactone, and acryloylethyl carbonic anhydride.

Suitable endcapping agents for polydiorganosiloxane oligourea segmentedcopolymers that would be amine terminated, if no endcapping agent werepresent, to provide terminal groups that are reactive under nmoisturecuring conditions include but are not limited to isocyanatopropyltrimethoxysilane, isocyanatopropyl triethoxysilane, isocyanatopropyldimethoxy (methylethylketoximino)silane, isocyanatopropyl diethoxy(methylethylketoximino)silane, isocyanatopropyl monomethoxydi(methylethylketoximino)silane, isocyanatopropyl monoethoxydi(methylethylketoximino)silane, and isocyanatopropyltri(methylethylketoximino)silane. Polyisocyanates that serve to form thecopolymer, may also serve as the moisture curable terminal portion ofthe copolymer when the number of isocyanate groups provided by thepolyisocyanates exceed the amine groups provided by the polyamines.Polymers prepared with such end-capping agents can be further reacted toprovide higher molecular weight polymers or copolymers.

Suitable endcappiug agents for polydiorganosiloxane oligourea segmentedcopolymers that would be isocyanate terminated if no endcapping agentwere present to provide terminal groups that are reactive under moisturecuring conditions include but are not limited by aminopropyltrimethoxysilane, aminopropyl triethoxysilane, aminopropylmethyldimethoxysilane, aminopropyl methyldiethoxysilane, aminopropyldimethoxy(methylethylketoximino)silane, aminopropyldiethoxy(methylethylketoximino)silane, aminopropylmonomethoxydi(methylethylketoximino)silane, aminopropylmonoethoxydi(methylethylketoximino)silane, and aminopropyltri(methylethylketoximino)silane mixtures thereof and partialhydrolyzates thereof. Preferred endcapping agents, forisocyanate-terminated polydiorganosiloxane polyurea segmented oligomers,if no end-capping agents were present to provide terminal groups thatare reactive under various conditions, include those selected from thegroup consisting of aminopropyl trimethoxysilane, aminopropyltriethoxysilane and aminopropyl methyldiethoxysilane.

Polydiorganosiloxane diamines useful in the present invention can berepresented by the formula

R, Y, D and p are defined as above and includes those having numberaverage molecular weights in the range of about 700 to 150,000.

Preferred diamines are substantially pure polydiorganosiloxane diaminesprepared as described in U.S. Pat. No. 5,214,119, wherein suchdescription is incorporated herein by reference. High puritypolydiorganosiloxane diamines are prepared from the reaction of cyclicorganosiloxanes and bis(aminoalkyl)disiloxanes utilizing an anhydrousamino alkyl functional silanolate catalyst such as tetramethylammonium3-aminopropyldimethylsilanolate, preferably in an amount less than 0.15weight percent based on the total weight of the cyclic organosiloxaneswith the reaction run in two stages.

Particularly preferred are polydiorganosiloxane diamines prepared usingcesium and rubidium catalysts.

Preparation includes combining under reaction conditions

(1) an amine functional end-capping agent represented by the formula:

 wherein each R, Y, D andp are defined as above and x is an integer ofabout 0 to 150;

(2) sufficient cyclic siloxane to obtain a polydiorganosiloxane diaminehaving a molecular weight greater than the molecular weight of theend-capping agent and

(3) a catalytically effective amount of cesium hydroxide, rubidiumhydroxide, cesium silanolate, rubidium silanolate, cesiumpolysiloxanolate, rubidium polysiloxanolate, and mixtures thereof.

The reaction is continued until substantially all of the aminefunctional end-capping agent is consumed. Then the reaction isterminated by adding a volatile organic acid to form a mixture of apolydiorganosiloxane diamine usually having greater than about 0.01weight percent silanol impurities and one or more of the following, acesium salt of the organic acid, a rubidium salt of the organic acid, orboth such that there is a small molar excess of organic acid in relationto catalyst. Then, the silanol groups of the reaction product arecondensed under reaction conditions to form polydiorganosiloxane diaminehaving less than or equal to about 0.01 weight percent silanolimpurities while the unreacted cyclic siloxane is stripped, and,optionally, the salt is removed by subsequent filtration.

Examples of polydiorganosiloxane diamines useful in the presentinvention include polydimethylsiloxane diamine, polydiphenylsiloxanediamine, polytrifluoropropylmethylsiloxane diamine,polyphenylmethylsiloxane diamine, polydiethylsiloxane diamine,polydivinylsiloxane diamine, polyvinylmethylsiloxane diamine,poly(5-hexenyl)methylsiloxane diamine, mixtures and copolymers thereof.

Examples of organic polyamines useful in the present invention includebut are not limited to polyoxyalkylene diamine, such as D-230, D-400,D-2000, D-4000, DU-700, ED-2001 and EDR-148, all available fromHuntsman, polyoxyalkylene triamine, such as T-3000 and T-5000 availablefrom Huntsman, polyalkylenes, such as Dytek A and Dytek EP, availablefrom DuPont.

The above polyamines, polyisocyanates, and endcapping agents are used inthe appropriate stoichiometric ratios to obtain curablepolydiorganosiloxane oligourea segmented copolymers with the desiredaverage degree of polymerization.

Silane agents may be used to crosslink the moisture curable polysiloxaneoligourea segmented copolymers of the present invention. Suitable silaneagents generally have the formula R″_(n)SiW_(4-n) where R″ is amonovalent hydrocarbon group, (for example, an alkyl, alkylenyl, aryl,or alkaryl group), n is 0, 1 or 2, and W is a monovalent hydrolyzablegroup such as a dialkylketoximino group, (for example,methylethylketoximino, dimethylketoximino, or diethylketoximino), alkoxygroup (for example, methoxy, ethoxy, or butoxy), alkenoxy group (forexample, isopropenoxy), acyloxy group (for example, acetoxy), alkamidogroup (for example, methylacetamido or ethylacetamido), or acylamidogroup (for example, phthalimidoamido). Silane crosslinking agentsfalling within this category are commercially available, for example,from Silar Laboratories, Scotia, N.Y. Particularly preferred silanecrosslinking agents are dialkylketoximinosilanes because they exhibitgood shelf-stability and do not form deleterious by-products upon cure.Examples include methyltri(methylethylketoximino) silane andvinyltri(methylethylketoximino) silane, both of which are commerciallyavailable from Allied-Signal, Inc. Morristown, N.J., and alkoxysilanesavailable from OSi Chemicals, Lisle, Ill.

The free radically curable polydiorganosiloxane oligourea segmentedcopolymer compositions of the invention can, depending upon theirviscosity, be coated, extruded, or poured, and rapidly, completely, andreliably radiation cured to elastomers (even at high molecular weight)by exposure to electron beam, visible or ultraviolet radiation. Curingshould be carried out in as oxygen-free an environment as possible,e.g., in an inert atmosphere such as nitrogen gas or by utilizing abarrier of radiation-transparent material having low oxygenpermeability. Curing can also be carried out under an inerting fluidsuch as water. When visible or ultraviolet radiation is used for curing,the silicone compositions may also contain at least one photoinitiator.Suitable photoinitiators include benzoin ethers, benzophenone andderivatives thereof, acetophenone derivatives, camphorquinone, and thelike. Photoinitiator is generally used at a concentration of from about0.1% to about 5% by weight of the total polymerizable composition, and,if curing is carried out under an inerting fluid, the fluid ispreferably saturated with the photoinitiator or photoinitiators beingutilized in order to avoid the leaching of initiator from the siliconecomposition. The rapid cure observed for these materials allows for theuse of very low levels of photoinitiator relative to what is known inthe art, hence uniform cure of thick sections can be achieved due todeeper penetration of radiation. If desired, the silicone compositionsof this invention can also be cured thermally, requiring the use ofthermal initiator such as peroxides, azo compounds, or persulfatesgenerally at a concentration of from about 1% to about 5% by weight ofthe total polymerizable composition. Preferably any thermal orphoto-initiator used is soluble in the silicone compositions themselves,requiring little or no use of a solvent to dissolve the initiator.

Examples of suitable curing catalysts for moisture curablepolydiorganosiloxane oligourea segmented copolymers include alkyl tinderivatives (e.g., dibutyltindilaurate, dibutyltindiacetate, anddibutyltindioctoate commercially available as “T-series Catalysts” fromAir Products and Chemicals, Inc. of Allentown, Pa.), and alkyl titanates(e.g., tetraisobutylorthotitanate, titanium acetylacetonate, andacetoacetic ester titanate commercially available from DuPont under thedesignation “TYZOR”). In general, however, it is preferred to selectsilane crosslinking agents that do not require the use of curingcatalysts to avoid reducing shelf-life and adversely affecting thephysical properties of the composition.

Other catalysts useful for moisture curable polydiorganosiloxaneoligourea segmented copolymers include acids, anhydrides, and loweralkyl ammonium salts thereof that include but are not limited to thoseselected from the group consisting of trichloroacetic acid, cyanoaceticacid, malonic acid, nitroacetic acid, dichloroacetic acid,difluoroacetic acid, trichloroacetic anhydride, dichloroaceticanhydride, difluoroacetic anhydride, triethylammonium trichloroacetate,trimethylammonium trichloroacetate, and mixtures thereof.

Also useful for curing compositions of this invention are the well knowntwo component room temperature free radical curatives consisting of apolymerization catalyst and an accelerator. Common polymerizationcatalysts useful in this two component curative include organicperoxides and hydroperoxides such as dibenzoyl peroxide, t-butylhydroperoxide, and cumene hydroperoxide, that are not active at roomtemperature in the absence of an accelerator. The accelerator componentof the curative consists of the condensation reaction product of aprimary or secondary amine and an aldehyde. Common accelerators of thistype are butyraldehyde-aniline and butyraldehyde-butylamine condensationproducts sold by E. I. duPont de Nemours & Co. as Accelerator 808™ andAccelerator 833™. This catalyst system may be employed to prepare atwo-part free radically curable organosiloxane oligourea segmentedcopolymer where the curable copolymrer is divided into two parts and toone part is added the polymerization catalyst and to the other part isadded the accelerator. Upon mixing this two component system cures atroom temperature. Alternatively, the polymerization catalyst can beincorporated in the free radically curable organosiloxane oligoureasegmented copolymer and the accelerator can be applied to a substratesuch that when the free radically curable organosiloxane oligoureasegmented copolymer containing polymerization catalyst contacts the“primed” substrate surface, cure proceeds immediately at roomtemperature. Those of ordinary skill in the art are familiar with suchcure systems and could readily adapt them to various productconstructions.

Fillers, tackifying resins, plasticizers, and other property modifiersmay be incorporated in the polydiorganosiloxane polyurea segmentedoligomers of the present invention. Generally, such modifiers are usedin amounts ranging up to about 80 weight percent. Additives such asdyes, pigments, stabilizers, antioxidants, compatibilizers, and the likecan also be incorporated into the polydiorganosiloxane polyureasegmented copolymers of the invention. Generally, such additives areused in amounts ranging up to about 20 weight percent.

Specific characteristics of the polydiorganosiloxane oligourea segmentedcopolymers of the invention can be influenced by a number of factorsincluding 1) the nature of the “K” group, when present, 2) the nature ofthe diisocyanate group used, 3) the molecular weight of thepolydiorganosiloxane monoamine and/or polydiorganosiloxane diamine used,4) the presence of an organic polyamine, 5) the average degree ofoligomerization, and 6) whether significant excesses of polyisocyanateor polyamine exist. The nature of the “K” group largely determineswhether or not the copolymer is curable, by what mechanism, and underwhat conditions.

The nature of the isocyanate residue in the polydiorganosiloxaneoligourea segmented copolymer influences stiffness and flow properties,and also affects the properties of the cured copolymers. Isocyanateresidues resulting from diisocyanates that form crystallizable ureas,such as tetramethyl-m-xylylene diisocyanate, 1,12-dodecane diisocyanate,dianisidine diisocyanate, provide copolymers that are stiffer than thoseprepared from methylenedicyclohexylene-4,4′-diisocyanate,3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate, and m-xylylenediisocyanate.

The molecular weight of the polydiorganosiloxane monoamine or diamine,if present, affects the elasticity of the polydiorganosiloxane oligoureasegmented copolymers. Lower molecular weight diamines result inpolydiorganosiloxane oligourea segmented copolymers having highermodulus and higher tensile strength when cured. Higher molecular weightdiamines provide copolymers having lower modulus but higher strain atbreak. The average degree of oligomerization affects the rheologicalproperties of the uncured oligomer and may affect the mechanicalproperties of the cured oligomer. The average degree of oligomerizationaffects the rheological properties with increasing degrees ofoligomerization. Excess polyisocyanate or polyamine may affect thereactivity of the oligomer with other reactive moieties.

The materials of the invention can be made by a solvent process and by asolventless process. In both processes of the present invention, thereactants and optional nonreactive additives are mixed in a reactor andallowed to react to form the polydiorganosiloxane polyurea segmentedoligomers having an average degree of oligomerization of from 2 to 12and that can then be removed from the reaction vessel. When isocyanatefunctional endcapping agents are utilized, such agents can, for example,be mixed with the other isocyanate reactants before they are introducedinto the reactor. Similarly, amine-functional endcapping agents forexample, may be mixed with polydiorganosiloxane diamine reactants beforethey are introduced into the reactor.

In the following discussion of the two processes, an isocyanatefunctional endcapping agent, different from the diisocyanate reactant,is utilized.

For the solvent based process, the reaction solvents and startingmaterials are usually purified and dried and the reaction is carried outunder an inert atmosphere such as dry nitrogen or argon.

The preferred reaction solvents are those that are unreactive with theisocyanate functional reactants, the amine functional reactants and theendcapping agents and that maintain the reactants and product completelyin solution throughout the polymerization reaction. Generally,chlorinated solvents, ethers, and alcohols are preferred with aliphaticdiisocyanates, with methylene chloride, tetrahydrofuran, and isopropylalcohol being particularly preferred. When reactants include aromaticdiisocyanates such as methylenediphenylene-4,4′-diisocyanate (MDI), amixture of tetrahydrofuran with 10% to 25% by weight of dipolar aproticsolvent such as dimethylformamide is preferred.

In the substantially solventless process, the flexibility of the processleads to interesting materials. One skilled in the art can expect theoptimum material for a particular application to be a function of thearchitecture and ratios of reactants, mixing speed, temperature, reactorthroughput, reactor configuration and size, residence time, residencetime distribution, optionai initiator architecture, and whether anyfillers, additives, or property modifiers are added.

Any reactor that can provide intimate mixing of the polyisocyanates andpolyamines is suitable for use in substantially solventless process ofthe present invention. The reaction may be carried out as a batchprocess using, for example, a flask equipped with a mechanical stirrer,provided the product of the reaction has a sufficiently low viscosity atthe processing temperature to permit mixing, or as a continuous processusing, for example a single screw or twin screw extruder. Preferably,the reactor is a wiped surface counter-rotating or co-rotating twinscrew extruder.

Temperatures in the reactor should be sufficient to permit reactionbetween the polyisocyanate and the polyamine to occur. The temperatureshould be sufficient to permit conveying of the materials through thereactor, and any subsequent processing equipment such as, for example,feedblocks and dies. For conveying the reacted material, the temperatureshould preferably be in the range of about 20 to 250° C., morepreferably in the range of about 20 to 200° C. Residence time in thereactor typically varies from about 5 seconds to 8 minutes, moretypically from about 15 seconds to 3 minutes.

The residence time depends on several parameters, including, forexample, the length to diameter ratio of the reactor, mixing rates,overall flowrates, reactants, and the need to blend in additionalmaterials. For materials involving reaction with minimal or no blendingof a nonreactive component, the reaction can easily take place in aslittle as 5:1 length to diameter units of a twin screw extruder.

When a wiped surface reactor is used, it preferably has relatively closeclearances between the screw flight lands and the barrel, with thisvalue typically lying between 0.1 to about 2 mm. The screws utilized arepreferably fully or partially intermeshing or fully or partially wipedin the zones where a substantial portion of the reaction takes place.

Because of the rapid reaction that occurs between the polyisocyanatesand polyamines, the materials are preferably fed into an extuder atunvarying rates, particularly when using higher molecular weightpolydiorganosiloxane amines, i.e., with number average molecular weightsof about 50,000 and higher. Such feeding generally reduces undesirablevariability of the final product.

One method of ensuring the continuous feeding of very low flowpolyisocyanate quantities in an extruder is to first mix the endcappingagent with the polyisocyanate and then to allow the polyisocyanate andisocyanate-functional endcapping agent feed line to touch or very nearlytouch the passing threads of the screws. Another method would be toutilize a continuous spray injection device that produces a continuousstream of fine droplets of the polyisocyanate and isocyanate-functionalendcapping agent into the reactor.

However, the various reactants and additives can be added in any orderprovided the addition of an additive does not interfere with thereaction of the reactants. An additive that is particularly reactivewith a polyisocyanate reactant typically would not be added until afterthe reaction of the polyisocyanate with a polyamine reactant. Further,the reactants can be added simultaneously or sequentially into thereactor and in any sequential order, for example, the polyisocyanatestream can be the first component added into the reactor in a mannersuch as mentioned above. Polyamine can then be added downstream in thereactor. Alternately, the polyisocyanate stream can also be added afterthe polyamine has been introduced into the reactor.

The process of the present invention has several advantages overconventional solution polymerization processes for makingpolydiorganosiloxane polyurea segmented copolymers such as (1) theability to vary the polyisocyanate-to-polyamine ratio to obtainmaterials with properties superior to solution polymerized materials,(2) the capabiility of polymerizing high molecular weight compositionsthat cannot be easily produced using solution polymerization, (3) theability to directly produce shaped articles with reduced heat histories,(4) the ability to directly blend in fillers, tackifying resins,plasticizers, and other property modifiers, and (5) the elimination ofsolvent.

The flexibility of altering the polyisocyanate-to-polyamine ratio in thecontinuous process is a distinct advantage. This ratio can be variedabove and below the theoretical value of 1:1 quite easily.

The polyisocyanate and isocyanate-functional endcapping agent stream canbe the first component added into the reactor in a manner such asmentioned above. The polydiorganosiloxane amine can then be addeddownstream in the reactor. Alternately, the diisocyanate and isocyanatefunctional endcapping agent stream can also be added after thepolydiorganosiloxane amine stream has been introduced into the reactor.

In formulating the polydiorganosiloxane oligourea segmented copolymerswith components such as tackifying resins, inorganic fillers,plasticizers or other materials essentially non-reactive with thepolydiorganosiloxane polyurea segmented oligomer reactants, thematerials to be blended can be added further downstream in the reactorafter a substantial portion of the reaction of the diisocyanate, thepolydiorganosiloxane amine, and the isocyanate functional endcappingagent has taken place. Another suitable order of addition is addition ofthe polydiorganosiloxane amine first, the additive second, and thediisocyanate and isocyanate functional endcapping agent third, with thediisocyanate and the endcapping agent fed in a continuous manner. If theadditive can be conveyed in the reactor, it can be added into thereactor first with the polydiorganosiloxane amine, diisocyanate, andisocyanate functional endcapping agent following separately at laterstages in the process.

The substantially solventless process of the present invention hasseveral advantages over conventional solution polymerization processesfor making polydiorganosiloxane oligourea segmented copolymers such asthe ability to directly produce shaped articles with reduced heathistories, the ability to directly blend in fillers, tackifying resins,and other property modifiers, and the elimination of solvent. Becausethe polydiorganosiloxane oligourea segmented copolymers of thisinvention typically have low melt viscosities, they can be processed atlower temperature than can fully chain extended analogs.

In general, long exposure to heat would be expected to degradepolydiorganosiloxane oligourea segmented copolymoers and leads to adegradation of physical properties. The degradation experienced bycertain solution polymerized polydiorganosiloxane oligourea segmentedcopolymers upon drying and subsequent hot melt extrusion is alsoovercome by the continuous process of the present invention becausereactively extruded polydiorganosiloxane oligourea segmented copolymerscan be extruded directly from the polymerization zone through a die toform shaped articles such as tubing and films without the additionalheat history associated with solvent removal and the subsequent oligomerreheating.

The ability to eliminate the presence of solvent during the reaction ofthe diisocyanate, the endcapping agent and the optionalpolydiorganosiloxane di or mono amine yields a much more efficientreaction. The average residence time using the process of the presentinvention is typically 10 to 1000 times shorter than that required insolution polymerization. A small amount of solvent can be added, ifnecessary, e.g., from about 0.5% up to about 5% of the totalcomposition, in this process either as a carrier for injecting otherwisesolid materials or in order to increase stability of an otherwise lowflowrate stream of material into the reaction chamber.

While the continuous solventless process for making the copolymers hasmany advantages over the solvent process, there may be some situationswhere the solvent process is preferred or where a combination of the twois preferred. In the later case, polydiorganosiloxane oligoureasegmented copolymer could be made by the continuous process andsubsequently mixed in solvent with thermal initiators, photoinitiators,tackifying resins, plasticizers and/or filler components.

The ability to eliminate the presence of solvent during the reaction ofpolyamine and polyisocyanate yields a much more efficient reaction. Theaverage residence time using the process of the present invention istypically 10 to 1000 times shorter than that required in solutionpolymerization. A small amount of non-reactive solvent can be added, ifnecessary, for example, from about 0.5% up to about 5% of the totalcomposition, in this process either as a carrier for injecting otherwisesolid materials or in order to increase stability of an otherwise lowflowrate stream of material into the reaction chamber.

This invention is further illustrated by the following examples that arenot intended to limit the scope of the invention. In the examples allparts and percentages are by weight unless otherwise indicated. Allmolecular weights reported are number average molecular weights ingrams/mol.

Titration of Polydiorganosiloxane and Organic Diamines

Multiple lots of some of the diamines were synthesized for variousexamples. The actual number average molecular weight ofpolydiorganosiloxane or organic diamines were determined by thefollowing acid titration. Sufficient diamine to yield about 1milliequivalent of amine is dissolved in 50/50 tetrahydrofuran/isopropylalcohol to form a 10% solution. This solution was titrated with 1.0Nhydrochloric acid with bromophenyl blue as an indicator to determinenumber average molecular weight The molecular weights are dependent onthe exact ratio of the reactants used in the diamine synthesis and theextent of stripping cyclic siloxanes. Remaining cyclics are diluentsthat increase the apparent molecular weight of polydiorganosiloxanediamine.

Preparation of Polydiorganosiloxane Diamines

Polydimethylsiloxane Diamine A

A mixture of 4.32 parts bis(3-aminopropyl)tetramethyl disiloxane and95.68 parts octamethylcyclotetrasiloxane, was placed in a batch reactorand purged with nitrogen for 20 minutes. The mixture was then heated inthe reactor to 150° C. Catalyst, 100 ppm of 50% aqueous cesiumhydroxide, was added and heating continued for 6 hours until thebis(3-aminopropyl) tetramethyl disiloxane had been consumed. Thereaction mixture was cooled to 90° C., neutralized with excess aceticacid in the presence of some triethylamine, and heated under high vacuumto remove cyclic siloxanes over a period of at least five hours. Thematerial was cooled to ambient temperature, filtered to remove anycesium acetate that had formed, and titrated with 1.0N hydrochloric acidto determine number average molecular weight. Two lots were prepared andthe molecular weights of Polydimethylsiloxane Diamine A were Lot 1:5280and Lot 2:5310.

Polydimethylsiloxane Diamine B

Polydimethylsiloxane diamine was prepared as described forPolydimethylsiloxane Diamine A except 2.16 partsbis(3-aminopropyl)tetramethyl disiloxane and 97.84 partsoctamethylcyclotetrasiloxane were used. Two lots were prepared. Themolecular weight of Polydimethylsiloxane Diamine B was 10,700.

Polydimethylsiloxane Diamine C

A mixture of 21.75 parts Polydimethylsiloxane Diamine A and 78.25 partsoctamethylcyclotetrasiloxane was placed in a batch reactor, purged withnitrogen for 20 minutes and then heated in the reactor to 150° C.Catalyst, 100 ppm of 50% aqueous cesium hydroxide, was added and heatingcontinued for 3 hours until equilibrium concentration of cyclicsiloxanes was observed by gas chromatography. The reaction mixture wascooled to 90° C., neutralized with excess acetic acid in the presence ofsome triethylamine, and heated under high vacuum to remove cyclicsiloxanes over a period of at least 5 hours. The material was cooled toambient temperature, filtered, and titrated with 1.0N hydrochloric acidto determine number average molecular weight. The molecular weight ofresulting Polydimethylsiloxane Diamine C was 22,300.

Polydimethylsiloxane Diamine D

Polydimethylsiloxane diamine was prepared as described forPolydimethylsiloxane Diamine C except 12.43 parts PolydiorganosiloxaneDiamine A and 87.57 parts octamethylcyclotetrasiloxane were used. Twolots were prepared. The molecular weights of the resultingPolydimethylsiloxane Diamine D were Lot 1-35,700 and Lot 2-37,800.

Polydimethylsiloxane Diamine E

Polydimethylsiloxane diamine was prepared as described forPolydimethylsiloxane Diamine C except that 8.7 partsPolydimethylsiloxane Diamine A and 91.3 partsoctamethylcyclotetrasiloxane were used. The molecular weight of thethus-produced Polydimethylsiloxane Diamine E was 50,200.

Polydiphenyldimethylsiloxane Diamine F

To a 3-necked round bottom flask fit with mechanical stirrer, staticnitrogen atmosphere, oil heating bath, thermometer, and refluxcondenser, were added 75.1 parts octamethylcyclotetrasiloxane, 22.43parts octaphenylcyclotetrasiloxane, and 2.48 partsbis(3-aminopropyl)tetramethyl disiloxane. Under static nitrogenatmosphere, the reactants were heated to 150° C. and degassed underaspirator vacuum for 30 seconds before restoring static nitrogenatmosphere. A charge of 0.2 grams cesium hydroxide solution (50%aqueous) was added to the flask and heating continued for 16 hours at150° C. The flask was cooled to ambient temperature and then 2 mLtriethylamine and 0.38 mL acetic acid were added. With good agitationflask was placed under a vacuum of 100 N/m² (100 Pa), heated to 150° C.,and maintained at 150° C. for 5 hours to remove volatile materials.After 5 hours heat was removed and contents cooled to ambienttemperature. The molecular weight of PolydiphenyldimethylsiloxaneDiamine F was 9620.

Preparation of Polydimethylsiloxane Monoamines

The following polydimethylsiloxane monoamines were synthesized forvarious examples according to the procedures of U.S. Pat. No. 5,091,483Example 6 (terminating agent) and Example 10 (silicone monoamine). Theactual number average molecular weight of the different lots aredetermined by acid titration.

Aminopropyldimethylfluorosilane Terminating Agent

To a 500 mL 3-necked round bottom flask was added 49.6 grams1,3-bis(3-aminopropyl)tetramethyldisiloxane, 29.6 grams ammoniumfluoride, and 300 mL cyclohexane. While heating under reflux, water wasremoved by means of Dean-Stark trap. After 18 hours, 4.4 mL of water wascollected, and the clear, colorless solution was transferred while warmto a 500 mL 1-neck round bottom flask. The solvent was removed on arotary evaporator to provide 165 grams of white solid. The solid wasdissolved in 200 ml methylene chloride, 30 grams of hexamethyldisilazane was added, and the mixture was stirred and heated underreflux for 5 hours. The mixture was filtered and the solvent removedunder aspirator vacuum. The product was distilled (boiling point of 70°C.) under aspirator vacuum to provide 3aminopropyldimethylfluorosilaneas a clear, colorless oil. The yield was 54 grams (100%), that wasdetermined to be pure by vapor phase chromatography. The structure wasconfirmed by NMR spectroscopy.

Polydimethylsiloxane Monoamine A

To 1.6 parts of 2.5 M n-butyl lithium were added 7.4 parts ofoctamethylcyclotetrasiloxane that had been purged with argon and themixture was then stirred for 30 minutes; 500 parts of 50%hexamethylcyclotrisiloxane in dry tetrahydrofuran was added and thereaction mixture stirred at room temperature for 18 hours until thepolymerization was complete. To the resulting viscous syrup was added3.4 parts 3-aminopropyldimethylfluorosilane terminating agent. Theviscosity rapidly decreased. After stirring for 2 hours, the solvent wasdistilled off on a rotary evaporator. The product was filtered to removelithium fluoride and provided Polydimethylsiloxane Monoamine A as aclear, colorless oil. The number average molecular weight ofPolydimethylsiloxane Monoamine A was 9800.

Polydimethylsiloxane Monoamine B

To 1.6 parts of 2.5 M n-butyl lithium were added 7.4 parts ofoctamethylcyclotetrasiloxane that had been purged with argon and themixture was then stirred for 30 minutes; 1000 parts of 50%hexamethylcyclotrisiloxane in dry tetrahydrofuran was added and thereaction mixture stirred at room temperature for 18 hours untilpolymerization was complete. To the resulting viscous syrup was added3.4 parts 3-aminopropyldimethylfluorosilane terminating agent. Theviscosity rapidly decreased. After stirring for 2 hours, the solvent wasdistilled off on a rotary evaporator. The product was filtered to removelithium fluoride and provided 500 Polydimethylsiloxane Monoamine B as aclear, colorless oil. The number average molecular weight was 20,600.

Polydimethylsiloxane Monoamine C

To 588 grams (2.64 mol) hexamethylcyclotrisiloxane which had beendegassed via boiling then cooled to room temperature was added 500 mLdry tetrahydrofuran. To this solution was added 19.3 mL (0.05 mol) of2.59 M n-butyl lithium and the reaction mixture stirred at roomtemperature for 6.5 hours until the polymerization was complete. To theresulting viscous syrup was added 23.2 mL (0.06 mol) of 2.58M3-aminopropyldimethyl fluorosilane terminating agent. After stirringovernight the solvent and remaining hexamethylcyclotrisiloxane weredistilled off on a rotary evaporator to afford the PolydimethylsiloxaneMonoamine C as a clear, colorless oil. The number average molecularweight of Polydimethylsiloxane Monoamine C was 12,121.

The following test methods were used to characterize thepolydiorganosiloxane oligourea segmented copolymers produced in thefollowing examples:

Sample Characterization

Characterization of Uncured Samples

Rheological properties of the uncured materials were determined usingRheometrics, RDA II Rheometer using dynamic temperature ramp mode (−30°C.-175° C.) at a ramp rate of 5° C., 25 mm parallel plates, a strain of2.0% and a frequency of 10.0 rad/s. Sample thickness was 1-2 mm.

The storage modulus, G′, represents that portion of the mechanicalenergy that is stored, i.e., completely recoverable, when theviscoelastic material undergoes cyclic deformation. The stored energy isanalogous to that seen in a simple spring going through cyclicdeformation.

The loss modulus, G″, represents that portion of the mechanical energydissipated, i.e., converted to heat, when the viscoelastic materialundergoes cyclic deformation. The dissipated energy is analogous to thatseen in a simple dashpot going through cyclic deformation.

Stress Rheometer, Rheometrics, DSR, was used to characterize shear creepviscosities of the uncured materials in step stress (creep) mode with 25mm parallel plates.

Characterization of Cured Samples

Free-radically curable materials were squeezed between two polyesterfilms to a thickness of approximately 1 mm and cured at an intensity of1.73 mW for a given length of time with low intensity ultravioletlights. Mechanical properties of the cured samples were characterized asfollows:

Mechanical testing was performed on an Instron Model 1122 tensiletester. Testing was performed according to a modification of ASTMD412-83. Samples were prepared according to Method B (cut ringspecimens). Type 1 rings (5.1 cm circumference) were produced with aspecially-designed precision ring cutter. The Instron analog outputsignal was routed to a digital voltmeter with accuracy better than 0.5percent and the digital readings were recorded by a computer.Modifications to the ASTM were as follows:

1. The crosshead speed was 12.7 cm/min rather than 50.8 cm/min.

2. The test fixture shafts (upper and lower jaw) both rotated at 30 RPMin the same direction in order to maintain uniform strain throughout theentire ring.

3. The thickness of the rings was 1 mm.

Molecular Weight

The weight average and number average molecular weights of selectedpolydimethylsiloxane oligourea segmented copolymers were determined viagel permeation chromatography with a HP 1090 Chromatograph equipped witha HP 1037 A Refractive Index detector, a Waters 590 pump, a Waters Wispauto-injector, and a Kariba column oven at R.T. The copolymer wasdissolved in DMF w/v 0.05% LiBr at 15 mg/5 mL, filtered with a 0.2micron nylon filter, and 100 microliters injected into a Jordi Mixed Bedcolumn. The elution rate was 0.5 mL/min in DMF+0.05% w/v LiBr.Calibration was based on Polystyrene standards from Pressure ChemicalCompany, Pittsburgh, Pa. thus reported molecular weights are thePolystyrene equivalents.

EXAMPLES

In the following Examples, all diisocyanates were used as received andthe diisocyanate:diamine ratios were calculated using the diisocyanatemolecular weight reported by the diisocyanate supplier and the diaminemolecular weight as determined by acid titration. In the Examples allparts and percentages are by weight unless otherwise indicated. Allmolecular weights reported are number average molecular weights ingrams/mole.

Examples 1-5

In Example 1, 40.0 parts (4.0 mmoles) of Polydimethylsiloxane MonoamineA, molecular weight 9,800, was degassed under vacuum at 100° C. and 0.49parts (2.0 mmoles) tetramethyl-m-xylylene diisocyanate in 5.0 partstoluene was added dropwise while stirring. Then 5 mL of 2-propanol wasadded to reduce the viscosity, and the resulting polydimethylsiloxaneoligourea segmented copolymer was poured into a Petri dish and airdried.

In Example 2, a polydimethylsiloxane oligourea segmented copolymer wasprepared as in Example 1, except 80.0 parts (3.90 mmoles) ofPolydimethylsiloxane Monoamine B, molecular weight 20,600 wassubstituted for Monoamine A.

In Example 3, a polydimethylsiloxane oligourea segmented copolymer wasprepared as in Example 1, except 0.46 parts (2.0 mmoles) of1,12-diisocyanatododecane was substituted for the tetramethyl-m-xylylenediisocyanate.

In Example 4, a polydimethylsiloxane oligourea segmented copolymer wasprepared as in Example 1, except 0.59 parts (2.0 mmoles)4,4′-diisocyanato-3,3′-dimethoxybiphenyl was substituted for thetetramethyl-m-xylylene diisocyanate.

In Example 5, a polydimethylsiloxane oligourea segmented copolymer wasprepared as in Example 1, except 0.52 parts (2.0 mmoles) ofmethylenedicyclohexylene-4,4′-diisocyanate was substituted for thetetramethyl-m-xylylene diisocyanate and 2-propanol was not added.

The storage modulus, G′, the loss modulus, G″, the crossover modulus andcrossover temperature were determined for the polydimethylsiloxaneoligourea segmented copolymers of Examples 1-4, each being gel-like andhaving an average degree of oligomerization of 2 and beingnon-functional. The copolymer of Example 5 flowed at room temperatureand, thus, had a shear creep viscosity too low to characterize by themethod used. The results are set forth in Table 1.

TABLE 1 G′ at G″ at Crossover Crossover 25° C. 25° C. Modulus Temp.Example (Pa) (Pa) (Pa) (° C.) 1 8.0 × 10⁴ 0.8 × 10⁴ — ˜140 2 10.0 × 10⁴0.28 × 10⁴ — 100 3 0.3 × 10⁴ 0.2 × 10⁴ 0.13 × 10⁴ 28 4 3.8 × 10⁴ 0.08 ×10⁴ 0.4 × 10⁴ 127

The data in Table 1 demonstrates that the polydimethylsiloxane oligoureasegmented copolymer prepared using aromatic or aromatic-aliphaticdiisocyanates, Examples 1 and 4, had higher storage moduli and crossovertemperature than the copolymer prepared using an aliphatic diisocyanate,Example 3. Further, the copolymers vary in storage modulus from 10×10⁴,indicating a firmer gel, to 0.3×10⁴, indicating a very soft gel, to aviscous liquid (Example 5).

Examples 6-10

In Example 6, a mixture of 79 parts (8.0 mmoles) of PolydimethylsiloxaneMonoamine A, molecular weight 9,800, and 21 parts (4.0 mmoles) ofPolydimethylsiloxane Diamine A, molecular weight 5280, was dissolved in69 parts toluene and 1.96 parts (8.0 mmoles) of tetramethyl-m-xylylenediisocyanate in 40 parts toluene was added dropwise under agitation atroom temperature. The resulting polydimethylsiloxane oligourea segmentedcopolymer was air dried.

In Example 7, a mixture of 57.9 parts (5.9 mmoles) ofPolydimethylsiloxane Monoamine A, molecular weight 9,800, and 15.6 parts(2.95 mmoles) of Polydimethylsiloxane Diamine A, molecular weight 5280,was dissolved in 75 parts toluene and 1.54 parts (5.9 mmoles) ofmethylenedicyclohexylene-4,4′-diisocyanate in 25 parts toluene was addeddropwise under agitation at room temperature The resultingpolydimethylsiloxane oligourea segmented copolymer was air dried.

In Example 8, a polydimethylsiloxane oligourea segmented copolymer wasprepared as in Example 6, except 1.98 parts (7.9 mmoles) of1,12-diisocyanatododecane was substituted for the tetramethyl-m-xylylenediisocyanate.

In Example 9, a mixture of 87.8 parts (4.25 mmoles) ofPolydimethylsiloxane Monoamine B, molecular weight 20,600 and 11.2 parts(2.12 mmoles) of Polydimethylsiloxane Diamine A, molecular weight 5280,was dissolved in 52 parts toluene and 1.04 parts (4.25 mmoles) oftetramethyl-m-xylylene diisocyanate in 34 parts toluene was addeddropwise under agitation at room temperature. The resultingpolydimethylsiloxane oligourea segmented copolymer was air dried.

In Example 10, a mixture of 65.8 parts (3.19 mmoles) ofPolydimethylsiloxane Monoamine B, molecular weight 20,800, and 8.4 parts(1.59 mmoles) of Polydimethylsiloxane Diamine A molecular weight 5280,was dissolved in 96 parts toluene and 0.80 parts (3.18 mmoles) of1,12-diisocyanatododecane diisocyanate in 22 parts toluene was addeddropwise under agitation at room temperature. The resultingpolydimethylsiloxane oligourea segmented copolymer was air dried.

The polydimethylsiloxane oligourea segmented copolymers of each ofExamples 6-10 had an average degree of oligomerization of 3. Thecopolymers of Examples 6, 8, 9 and 10 exhibited no cold flow, that is,did not change shape at ambient conditions, while the copolymer ofExample 7 did exhibit cold flow. The storage modulus, G′, loss modulus,G″, crossover modulus and crossover temperature were determined for thepolydimethylsiloxane oligourea segmented copolymers of Examples 6-10.The results are set forth in Table 2.

TABLE 2 G′ at G″ at Crossover Crossover 25° C. 25° C. Modulus Temp.Example (Pa) (Pa) (Pa) (° C.) 6 20 × 10⁴ 3.0 × 10⁴ 5 × 10⁴ 141 7 6.0 ×10⁴ 2.0 × 10⁴ 2.7 × 10⁴ 45 8 13 × 10⁴ 1.7 × 10⁴ 0.5 × 10⁴ 53 9 10 × 10⁴2.0 × 10⁴ nd* >150 10 29 × 10⁴ 3.0 × 10⁴ 1.2 × 10⁴ 47 *not determinable

Examples 11-15

In Example 11, a mixture of 3.25 parts (13.3 mmoles) oftetramethyl-m-xylylene diisocyanate, 3.93 parts (13.3 mmoles) ofn-octadecyl isocyanate dissolved in 17 parts toluene was added dropwiseunder agitation at room temperature to a solution of 105.5 parts (20mmoles) of Polydimethylsiloxane Diamine A molecular weight 5,280 in 50parts of toluene. The resulting polydimethylsiloxane oligourea segmentedcopolymer was air dried.

In Example 12, a mixture of 3.35 parts (13.3 mmoles) of1,12-diisocyanatododecane and 3.93 parts (13.3 mmoles) of n-octadecylisocyanate dissolved in 29 parts toluene was added dropwise underagitation at room temperature to a solution of 105.5 parts (20 mmoles)of Polydimethylsiloxane Diamine A molecular weight 5,280 in 46 parts oftoluene. The resulting polydimethylsiloxane oligourea segmentedcopolymer was air dried.

In Example 13, a mixture of3.41 parts (13.3 mmoles) ofmethylenedicyclohexylene-4,4′-diisocyanate and 3.93 parts (13.3 mmoles)of n-octadecyl isocyanate dissolved in 29 parts toluene was addeddropwise under agitation at room temperature to a solution of 105.5parts (20 mmoles) of Polydimethylsiloxane Diamine A molecular weight5,280 in 46 parts of toluene. The resulting polydimethylsiloxaneoligourea segmented copolymer was air dried.

In Example 14, a mixture of 3.25 parts (13.3 mmoles) oftetramethyl-m-xylylene diisocyanate and 1.58 parts (13.3 mmoles) ofphenyl isocyanate dissolved in 11.5 parts toluene was added dropwiseunder agitation at room temperature to a solution of 105.5 parts (20mmoles) of Polydimethylsiloxane Diamine A molecular weight 5,280 in 95parts of toluene. The resulting polydimethylsiloxane oligourea segmentedcopolymer was air dried.

In Example 15, a polydimethylsiloxane oligourea segmented copolymer wasprepared as in Example 14, except a mixture of 3.35 parts (13.3 mmoles)of 1,12-diisocyanatododecane was substituted for thetetramethyl-m-xylylene diisocyanate.

The polydimethylsiloxane oligourea segmented copolymers of Examples11-15 had an average degree of oligomerization of 3, with Examples 11-12and 14-15 exhibiting no cold flow, while Example 13 did exhibit coldflow. The storage modulus, G′, the loss modulus, G″, the crossovermodulus and crossover temperature were determined for Examples 11-15.The results are set forth in Table 3.

TABLE 3 G′ at G″ at Crossover Crossover 25° C. 25° C. Modulus Temp.Example (Pa) (Pa) (Pa) (° C.) 11 100 × 10⁴ 34 × 10⁴ 1.5 × 10⁴ 116 12 200× 10⁴ 18 × 10⁴ ˜1 × 10⁴ 42 13 14 × 10⁴ 10 × 10⁴ 6 × 10⁴ 34 14 190 × 10⁴17 × 10⁴ 0.2 × 10⁴ 145 15 50 × 10⁴ 7 × 10⁴ 2 × 10⁴ 48

The polydimethylsiloxane oligourea segmented copolymers prepared usingn-octadecylisocyanate exhibited higher loss modulus and lower crossovertemperatures than copolymers prepared using phenyl isocyanate as theend-capper.

Copolymers prepared with tetramethyl-m-xylylene diisocyanate possesshigher loss modulus and higher crossover temperature than copolymersprepared with 1,12-diisocyanatododecane.

Example 16

In Example 16, 60.3 parts (2.71 mmoles) of Polydimethylsiloxane DiamineC, molecular weight 22,300, was dissolved in 202 parts methylenechloride, and added dropwise to a solution of 0.9 parts (3.62 mmoles) ofmethylenediphenylene-4,4′-diisocyanate in 25 parts methylene chlorideunder agitation at room temperature. The resulting solution was dried ina vacuum oven at room temperature. The resulting isocyanate-terminatedpolydimethylsiloxane oligourea segmented copolymer having an averagedegree of oligomerization of 3, was an insoluble, elastomeric material.

Examples 17-28 Example 17

In Example 17, 52.76 parts (10.00 mmoles) Polydimethylsiloxane Diamine Amolecular weight 5280, was dissolved in 50 parts toluene, and a mixtureof 1.62 parts (6.67 mmoles) 1,12-diisocyanatododecane and 1.03 parts(6.67 mmoles) isocyanatoethyl methacrylate (available as MOI from ShowaRhodia Chemicals, Tokyo, Japan) was dissolved in 48 parts toluene andslowly added at room temperature to the solution with vigorous stirring.1.0 part DAROCUR™ 1173 (a photoinitiator available from Ciba-Geigy,Hawthorne, N.Y.) was added per 100 parts copolymer solution. Thissolution was then divided into two portions.

The first portion of the resulting polydimethylsiloxane oligoureasegmented copolymer solution was poured into a Petri dish and stood atroom temperature until the solvent was evaporated. The storage modulus,G′, loss modulus, G″, crossover modulus, crossover temperature and shearcreep viscosity at 25° C. and 300 seconds shear time were determined.The results are set forth in Table 4.

Examples 18-22

In Examples 18-22, polydimethylsiloxane oligourea segmented copolymerswere prepared as in Example 17, except the 1,12-diisocyanatododecane,was substituted with:

1.97 parts (6.67 mmoles) 4,4′-diisocyanato-3,3′-dimethoxybiphenyl(Example 18)

1.67 parts (6.67 mmoles) of methylenediphenylene-4,4′-diisocyanate(Example 19)

1.75 parts (6.67 mmoles) of methylenedicyclohexylene-4,4′-diisocyanate(Example 20)

1.25 parts (6.67 mmoles) of m-xylylene diisocyanate (Example 21)

1.47 parts (6.67 mmoles) of 3-isocyanatomethyl-3,5,5-trimethylcyclohexylisocyanate (Example 22).

As described in Example 17, each of the copolymer solutions wereseparated into two portions. The first portion examples were dried atroom temperature and tested as described above. The results are setforth in Table 4.

TABLE 4 Shear creep G′ at G″ at Crossover Crossover viscosity 25° C. 25°C. Modulus Temp. at 25° C. Example (Pa) (Pa) (Pa) (° C.) (Pa · s)* 17 60× 10⁴ 7.0 × 10⁴ 0.35 × 10⁴ 43 >1 × 10⁹ (6 kPa) 18 1.9 × 10⁴ 0.9 × 10⁴0.5 × 10⁴ 117 7.2 × 10⁸ (6 kPa) 19 1.0 × 10⁴ 2.0 × 10⁴ 4.9 × 10⁴ 2 5.0 ×10⁵ (1 Pa) 20 1.7 × 10⁴ 3.0 × 10⁴ 5.0 × 10⁴ 6 5.7 × 10³ (1 Pa) 21 0.06 ×10⁴ 0.3 × 10⁴ 6.0 × 10⁴ −15 9.0 × 10² (1 Pa) 22 0.12 × 10⁴ 0.7 × 10⁴ 5.0× 10⁴ −15 7.5 × 10² (1 Pa) *300 seconds shear time; shear stress asindicated in parenthesis

The polydimethylsiloxane polyurea segmented oligomers of Examples 17 to22 had an average degree of oligomerization of 3. The copolymers ofExamples 17-19 exhibited no cold flow while the copolymers of Examples20-22 exhibited cold flow.

The shear creep viscosities of Examples 17-22 varied over a broad rangedepending on the diisocyanate used, ranging from 7.5×10² to >1×10⁹ Pa·s,some of these relatively low molecular weight polymers were semisolid atroom temperature, while others behaved like viscous liquids.Polydimethylsiloxane oligourea segmented copolymers with drasticallydifferent rheological properties can be made by selection of thediisocyanate used to prepare the copolymers.

Examples 23-28

Using the second portion provided in Examples 17-22, the solvent ofthese second portions of the resulting polydimethylsiloxane oligureasegmented copolymer solutions was evaporated. Separately, each copolymerwas squeezed between two release-coated polyester films, with therelease coating facing the copolymer, to a thickness of about 40 mils.Each sample was subjected to 1.73 mW of low intensity radiation for 20minutes to effect cure. The UV radiation was provided by GE F40BLultraviolet bulbs. Each film was removed from the release films and themechanical properties, modulus, stress at break, and strain at break,swelling after being submerged in tetrahydrofuran (THF) for 24 hourscalculated by weight, and extractables in the THF for the curedcopolymers were determined. The results are set forth in Table 5.

TABLE 5 Stress at Strain at Swelling in Modulus break break THFExtractables Example (MPa) (MPa) (%) (%) (%) 23 3.74 2.16 150 250 8.6 243.61 1.57 70 269 14.8 25 2.10 2.26 180 260 8.2 26 1.51 2.12 180 250 8.427 0.68 2.14 204 260 8.5 28 0.86 2.75 210 260 8.5

When cured, the polydimethylsiloxane oligourea segmented copolymerspossessed similar stress at break and elongation at break. Tensilemoduli of the cured materials that showed less tendency to flow whenuncured, Examples 23-25, were higher than for those with low shearviscosities, Examples 26-28.

Examples 29-30 Example 29

In Example 29, Polydimethylsiloxane Diamine A molecular weight 5280, wasfed at a rate of 6.22 g/min (0.00236 equivalents amine/min) into thefirst zone of an 18 mm co-rotating twin screw extruder (available fromLeistritz Corporation, Allendale, N.J.) and a mixture of 50.8 parts byweight tetramethyl-m-xylyene diisocyanate, 32.2 parts isocyanatoethylmethacrylate, and 17.0 parts DAROCUR™ 1173 was fed at a rate of 0.378g/min. (0.00236 equivalents isocyanate/min) into zone 6. The extruderhad a 40:1 length:diameter ratio and double-start fully intermeshingscrews throughout the entire length of the barrel, rotating at 200revolutions per minute. The temperature profile for each of the 90 mmzones was: zone 1 to 4-25° C.; zone 5-40° C.; zone 6-60° C.; zone 7-90°C.; zone 8-100° C.; and endcap-120° C. The resultant polymer wasextruded, cooled in air, and collected. The storage modulus, G′,crossover temperature and shear creep viscosity at 25° C. weredetermined. The loss modulus, G″, at 25° C. and crossover modulus werenot determinable. The results were as follows:

Storage modulus >20 × 10⁴ Pa Crossover temperature >170 Shear creepviscosity 3.0 × 10⁸ Pa · s at 6 kPa

Example 30

In Example 30, a portion of the copolymer of Example 29 was pressedbetween polyester films, subjected to ultraviolet irradiation and testedas in Examples 23-28. The results were as follows:

Modulus 3.59 MPa Stress at break 1.83 MPa Strain at break 140% Swellingin THF 285% Extractables in THF 11.9

Examples 31-36 Example 31

In Example 31, 100.0 parts (10.00 mmoles) Polydimethylsiloxane DiamineB, molecular weight10,700, was dissolved in 50.0 parts toluene, and amixture of 1.68 parts (6.67 mmoles) of 1,12-diisocyanatododecane, 1.03parts (6.67 mmoles) of isocyanatoethyl methacrylate, and 15.0 partstoluene was slowly added at room temperature to the solution withvigorous stirring for 2 hours. Then, about 10 parts of 2-propanol wasadded and stirring was continued for 5 hours. 0.50 part DAROCUR™ 1173per 100 parts of polydimethylsiloxane oligourea segmented copolymer wasthen to the copolymer solution. The polydimethylsiloxane oligoureasegmented copolymer solution was separated into two portions. The firstportion was poured into a Petri dish and let stand at room temperatureuntil the solvent was evaporated. The sample was tested as described inExample 17 and the results are set forth in Table 6.

Examples 32-33

In Example 32, a polydimethylsiloxane oligourea segmented copolymer wasprepared as in Example 31, except 100.0 parts (4.48 mmoles)Polydimethylsiloxane Diamine C, molecular weight 22,300 was substitutedfor Diamine B, and a mixture of 0.75 parts (2.99 mmoles) of1,12-diisocyanatododecane, 0.46 parts (2.99 mmoles) of isocyanatoethylmethacrylate, and 15.0 parts of 2-propanol was used.

In Example 33, a polydimethylsiloxane oligourea segmented copolymer wasprepared as in Example 31, except 100.0 parts (2.64 mmoles)Polydimethylsiloxane Diamine D (Lot 2), molecular weight 37,800, weresubstituted for Diamine B and a mixture of 0.43 parts (1.73 mmoles) of1,12-diisocyanatododecane, 0.27 parts (1.73 mmoles) of isocyanatoethylmethacrylate, and 15.0 parts of 2-propanol was used.

The storage modulus, G′, the loss modulus, G″, the crossover modulus,the crossover temperature and the shear creep viscosity at 25° C. weredetermined for the polydimethylsiloxane oligourea segmented copolymersof Examples 32-33, each having an average degree of oligomerization of3. The results, together with those for Examples 17 and 31, are setforth in Table 6.

TABLE 6 Shear creep G′ at G″ at Crossover Crossover viscosity 25° C. 25°C. Modulus Temp. at 25° C. Example (Pa) (Pa) (Pa) (° C.) (Pa · s)* 17 60× 10⁴ 7.0 × 10⁴ 0.35 × 10⁴ 43 >1 × 10⁹ (6 kPa) 31 10 × 10⁴ 5.0 × 10⁴ 0.5× 10⁴ 44 8.4 × 10⁷ (50 Pa) 32 0.9 × 10⁴ 1.2 × 10⁴ 1.3 × 10⁴ 18 7.5 × 10³(1 Pa) 33 1.3 × 10⁴ 1.3 × 10⁴ 13 × 10⁴ 25 7.4 × 10³ (1 Pa) *300 secondsshear time; shear stress as indicated

The results in Tables 6 indicate that two opposite factors affected therheology of the copolymers of Examples 17 and 31-33. As the molecularweight of silicone diamine increased, the overall molecular weight ofthe polymer increased, while the concentration of the urea linkagesdecreased. In the examples, the latter factor predominated, as shearcreep viscosity decreased with increasing molecular weight of thepolydimethylsiloxane diamine.

Examples 34-36

In Examples 34-36, using the second portion samples of Examples 31-33,the copolymer solution for each copolymer prepared was air dried onpolyester release liner. These Examples were prepared and cured asdescribed in Example 23.

Once cured, the films were removed, the mechanical properties, modulusand stress at break and strain at break, swelling after being submergedin tetrahydrofuran (THF) for 24 hours calculated by weight, andextractables in the THF for each cured copolymer were determined. Theresults, together with those for Example 23 are set forth in Table 7.

TABLE 7 Stress at Strain at Swelling in Modulus break break THFExtractables Example (MPa) (MPa) (%) (%) (%) 23 3.74 2.16 150 250 8.6 340.86 1.17 230 370 19.7 35 0.38 0.59 380 500 9.8 36 0.23 0.67 660 70014.8

As can be seen from the data in Table 7, the tensile modulus of thecopolymer prepared using lower molecular weight polydimethylsiloxanediamine (Example 23) was much higher than for the copolymers in thathigher molecular weight polydimethylsiloxane diamines were used.

Examples 37-42 Example 37

In Example 37, 60 parts (6.00 mmoles) Polydimethylsiloxane Diamine B,molecular weight 10,700, was dissolved in a mixture of 100 partstoluene, 20 parts 2-propanol and a mixture of 0.98 parts (4.00 mmoles)of tetramethyl-m-xylylene diisocyanate, and 0.62 parts (4.00 mmoles) ofisocyanatoethyl methacrylate, and 15.0 parts toluene was slowly added atroom temperature to the solution with vigorous stirring for 2 hours.Then, about 10 parts of 2-propanol was added and stirring was continuedfor 5 hours. 0.50 part DAROCUR™ 1173 per 100 parts ofpolydimethylsiloxane oligourea segmented copolymer was then added to thecopolymer. This solution was separated into two portions. One of theportions of the polydimethylsiloxane oligourea segmented copolymersolution was poured into a Petri dish and was allowed to stand at roomtemperature until the solvent was evaporated. The sample was tested asdescritbed in Example 17 and the results are set forth in Table 8.

Examples 38-39

In Example 38, a polydimethylsiloxane oligourea segmented copolymer wasprepared as in Example 37, except a mixture of 15.84 parts (3.00 mmoles)Polydimethylsiloxane Diamine A molecular weight 5280, and 66.97 parts(3.00 mmoles) Polydimethylsiloxane Diamine C, molecular weight 22,300,dissolved in 69.00 parts toluene was substituted for Diamine B, and amixture of 0.98 parts (4.00 mmoles) of tetramethyl-m-xylylenediisocyanate and 0.62 parts (4.00 mmoles) of isocyanatoethylmethacrylate was used.

In Example 39, a polydimethylsiloxane oligourea segmented copolymer wasprepared as in Example 37, except 107.1 parts (3.00 mmoles)Polydimethylsiloxane Diamine D, molecular weight 35,700, weresubstituted for Diamine B and dissolved in a mixture of 100 partstoluene, and 10 parts 2-propanol, and a mixture of 0.49 parts (2.00mmoles) of tetramethyl-m-xylylene diisocyanate and 0.31 parts (2.00mmoles) of isocyanatoethyl methacrylate was used.

The storage modulus, G′, the loss modulus, G″, the crossover modulus,the crossover temperature, and the shear creep viscosity at 25° C. weredetermined for the polydimethylsiloxane oligourea segmented copolymersof Examples 38-39, each having an average degree of oligomerization of3. The results are set forth in Table 8.

TABLE 8 Shear creep Ex- G′ at G″ at Crossover Crossover viscosity at am-25° C. 25° C. Modulus Temp. 25° C. ple (Pa) (Pa) (Pa) (° C.) (Pa · s)*37 1.2 × 10⁴ 2.0 × 10⁴ 0.01 × 10⁴ 135 5.0 × 10⁶ (20 Pa) 38 7.0 × 10⁴ 4.1× 10⁴ 0.3 × 10⁴ 139 1.2 × 10⁶ (10 Pa) 39 4.0 × 10⁴ 2.3 × 10⁴ 1.9 × 10⁴50 1.5 × 10⁵ (1 Pa) *300 seconds shear time; shear stress as marked

The data in Table 8 demonstrate that by using blends of diamines,improved properties can be obtained. The copolymer of Example 38,prepared using a polydimethylsiloxane diamine having a number averagemolecular weight of 13,800 and prepared from a blend ofpolydimethylsiloxane diamines having molecular weights of 5,280 and22,300, possessed a storage modulus, loss modulus and a crossovertemperature above what would be predicted based on the data for thecopolymers of Examples 37 and 39.

Examples 40-42

In Examples 40-42, using the second portion samples of Examples 37-39,the copolymer solution for each copolymer prepared, was air dried onpolyester release liner. These Examples were prepared and cured asdescribed in Example 23.

Once cured, the films were removed and the mechanical properties,modulus, stress at break, strain at break, swelling after beingsubmerged in tetrahydrofuran (THF) for 24 hours calculated by weight,and extractables in the THF for each cured copolymers were determined.The results are set forth in Table 9.

TABLE 9 Stress at Strain at Swelling Modulus break break in THFExtractables Example (MPa) (MPa) (%) (%) (%) 40 1.06 1.14 230 360 19.741 1.03 1.87 380 460 9.7 42 0.33 0.70 620 670 13.0

The data in Table 9 shows that as the molecular weight of thepolydiorganosiloxane diamine increased stress at break decreased andelongation at break increased. Example 41 shows that copolymers withhigh stress at break and high elongation at break can be obtained usinga blend of polydimethylsiloxanes, that is, 5280 and 22,300 molecularweights.

Examples 43-48 Example 43

In Example 43, 500 parts (43.0 mmoles) Polydimethylsiloxane Diamine B,molecular weight 10,700, was dissolved in a mixture of 300 parts tolueneand a mixture of 7.51 parts (28.7 mmoles) ofmethylenedicyclohexylene-4,4′-diisocyanate, and 4.44 parts (28.7 mmoles)of isocyanatoethyl methacrylate, and 200 parts toluene was slowly addedat room temperature to the solution with vigorous stirring for 2 hours.Then, about 50 parts of 2-propanol was added and stirring was continuedfor 5 hours. 0.50 part DAROCUR™ 1173 per 100 parts ofpolydimethylsiloxane oligourea segmented copolymer was then added to thecopolymer. This solution was separated into two portions. One of theportions of the polydimethylsiloxane oligourea segmented copolymersolution was poured into a Petri dish and was allowed to stand at roomtemperature until the solvent was evaporated. The sample was tested asdescribed in Example 17 and the results, including those of Example 20are set forth in Table 10.

Examples 44-45

In Example 44, a polydimethylsiloxane oligourea segmented copolymer wasprepared as in Example 43, except 600 parts (27.0 mmoles)Polydimethylsiloxane Diamine C, molecular weight 22,300, weresubstituted for Diamine B and dissolved in 404 parts toluene, and amixture of 4.71 parts (19.0 mmoles) of methylenedicyclohexylene-4,4′-diisocyanate and 2.79 parts (18.0 mmoles) ofisocyanatoethyl methacrylate dissolved in 195 parts toluene were used.

In Example 45, a polydimethylsiloxane oligourea segmented copolymer wasprepared as in Example 43, except 100 parts (2.01 mmoles)Polydimethylsiloxane Diamine E, molecular weight 50,200, dissolved in123 parts toluene were substituted for Diamine B, and a mixture of 0.35parts (1.34 mmoles) or methylenedicyclohexylene-4,4′-diisocyanate and0.21 parts (1.34 mmoles) of isocyanatoethyl methacrylate dissolved in 56parts toluene was used.

The storage modulus, G′, the loss modulus, G″, the crossover modulus,the crossover temperature and the shear creep viscosity at 25° C. weredetermined for the polydimethylsiloxane oligourea segmented copolymersof Examples 44-45, each having an average degree of oligomerization of3. The results are set forth, together with those for Example 20 inTable 10.

TABLE 10 Shear creep Ex- G′ at G″ at Crossover Crossover viscosity atam- 25° C. 25° C. Modulus Temp. 25° C. ple (Pa) (Pa) (Pa) (° C.) (Pa ·s)* 20 1.7 × 10⁴ 3.0 × 10⁴ 5.0 × 10⁴ 6 5.7 × 10³ (1 Pa) 43 4.0 × 10⁴ 3.0× 10⁴ 2.8 × 10⁴ 35 1.7 × 10⁴ (1 Pa) 44 4.0 × 10⁴ 2.2 × 10⁴ 1.8 × 10⁴ 682.7 × 10⁴ (1 Pa) 45 3.8 × 10⁴ 1.8 × 10⁴ 1.4 × 10⁴ 65 — *300 secondsshear time; shear stress as marked

The data in Table 10 demonstrates that with increasing molecular weightof the polydimethylsiloxane diamine used, the crossover modulusdecreased while the crossover temperature generally increased.

Examples 46-48

In Examples 46-48, using the second portion samples of Examples 43-45,respectively the copolymer solution for each copolymer prepared was airdried on polyester release liner. These Examples were prepared and curedas described in Example 23.

Once cured, the films were removed and the mechanical properties, thatis, modulus and stress at break and strain at break; swelling afterbeing submerged in tetrahydrofuran (THF) for 24 hours calculated byweight, and extractables in the THF for each cured copolymer weredetermined. The results, together with those for Example 23 are setforth in Table 11.

TABLE 11 Stress at Strain at Swelling Modulus break break in THFExtractables Example (MPa) (MPa) (%) (%) (%) 26 1.51 2.12 180 250 8.4 460.68 1.54 294 418 10.5 47 0.54 0.81 343 540 6.8 48 0.22 0.62 882 1260 21

The data in Table 11 demonstrates that as molecular weight of thepolydimethylsiloxane increased, the modulus and stress at breakdecreased while the strain at break increased. Increasing molecularweight of the diamine also inhibited cure somewhat with 26% extractableswhen the diamine having a number average molecular weight of 49,700 wasused.

Examples 49-50 Example 49

In Example 49, a polydimethylsiloxane oligourea segmented copolymer wasprepared as in Example 29, except a mixture of 27.5 parts ofmethylenedicyclohexylene-4,4′-diisocyanate, 16.3 parts ofisocyanatoethyl methacrylate, and 56.3 parts of DAROCUR™ 1173 was fed ata rate of 0.105 g/min (0.000330 equivalents isocyanate/min) into thefirst zone and Polydimethylsiloxane Diamine D, Lot 1, molecular weight35,700, was fed at a rate of 6.2 g/min (0.000164 mol/min) in to thesixth zone. The rheological properties were as follows:

Storage modulus 3.1 × 10⁴ Pa Loss modulus 2.0 × 10⁴ Pa Crossover modulus1.6 × 10⁴ Pa Crossover temperature 65° C. Shear creep viscosity 3.8 ×10⁴ Pa

Example 50

In Example 50, the polydimethylsiloxane oligourea segmented copolymerprepared in Example 49 was exposed to 1.73 mW for 20 minutes lowintensity ultraviolet irradiation as in Example 30. The mechanicalproperties and the swelling, calculated by weight, and extractablesafter immersion in tetrahydrofuran (THF) were as follows:

Modulus 0.25 MPa Stress at break 0.46 MPa Strain at break 621% Swelling1050% Extractables 26%

Examples 51-54 Examples 51-52

In Example 51, a polydimethylsiloxane oligourea segmented copolymer wasprepared as in Example 31, except 105.52 parts (20.00 mmoles)Polydimethylsiloxane Diamine A molecular weight 5280, in 100.00 partstoluene, a mixture of 3.84 parts (15.74 mmoles) oftetramethyl-m-xylylene diisocyanate and 1.24 parts (7.99 mmoles) ofisocyanatoethyl methacrylate in 15 parts toluene, and 20.00 parts2-propanol were used.

In Example 52, a polydimethylsiloxane oligourea segmented copolymer wasprepared as in Example 51, except a mixture of 4.40 parts (18.00 mmoles)of tetramethyl-m-xylylene diisocyanate and 0.62 parts (3.99 mmoles) ofisocyanatoethyl methacrylate in 15 parts toluene was used.

The polydimethylsiloxane oligourea segmented copolymers of Examples 51and 52 had degrees of polymerization of 5 and 10, respectively.

The storage modulus, G′, loss modulus, G″, crossover modulus, andcrossover temperature were determined for Examples 51 and 52. The shearcreep viscosity could not be measured for these copolymers as they wereabove the limit of the test instrument. The results are set forth inTable 12.

TABLE 12 Crossover Crossover G′ at 25° C. G″ at 25° C. Modulus Temp.Example (Pa) (Pa) (Pa) (° C.) 51  33 × 10⁴  7 × 10⁴ 30 × 10⁴ 115 52 100× 10⁴ 20 × 10⁴ ˜0.1 × 10⁴ 163

The data in Table 12 demonstrates that as the average degree ofoligomerization increased from 5 to 10, the loss modulus increased andthe crossover modulus decreased.

Examples 53-54

In Examples 53-54, using the second portion samples of Examples 51-52,respectively, and the copolymers were subjected to 1.73 mW for 20minutes low intensity ultraviolet radiation to effect cure. Therheological characteristics were as set forth in Table 13.

TABLE 13 Stress at Strain at Swelling Modulus break break in THFExtractables Example (MPa) (MPa) (%) (%) (%) 53 4.70 1.69 160 390 20.254 4.97 1.38 190 ˜600 45

The copolymers were curable, but as the average degree ofoligomerization increased the cure was less efficient, as indicated bythe high content of extractables.

Examples 55-56

In Example 55 a polydimethylsiloxane oligourea segmented copolymer wasprepared as in Example 51, except a mixture of 4.19 parts (16.00 mmoles)of methylenedicyclohexylene-4,4′-diisocyanate and 1.24 parts (8.00mmoles) of isocyanatoethyl methacrylate in 15 parts toluene was used.

In Example 56, a polydimethylsiloxane oligourea segmented copolymer wasprepared as in Example 31, except a mixture of 4.72 parts (18.00 mmoles)of methylenedicyclohexylene-4,4′-diisocyanate and 0.62 parts (4.00mmoles) of isocyanatoethyl methacrylate in 15 parts toluene was used.

The copolymers of Examples 55-56 had average degrees of polymerizationof 5 and 10, respectively. The storage modulus, G′, the loss modulus,G″, the crossover temperature, and the shear creep viscosity of thecopolymers of Examples 55 and 56, together with those of Example 20 thatwas prepared using the same reactants but in proportions such that thedegree of oligomerization was 3, are set forth in Table 14.

TABLE 14 Shear creep Ex- G′ at G″ at Crossover Crossover viscosity atam- 25° C. 25° C. Modulus Temp. 25° C. ple (Pa) (Pa) (Pa) (° C.) (Pa ·s)* 20  1.7 × 10⁴ 3.0 × 10⁴ 5.0 × 10⁴ 6 5.7 × 10³ (1 Pa) 55 12.0 × 10⁴8.0 × 10⁴ 7.0 × 10⁴ 36 2.8 × 10³ (1 Pa) 56 27.0 × 10⁴ 9.0 × 10⁴ 5.0 ×10⁴ 83 7.3 × 10⁶ (6 kPa) *300 seconds shear time; shear stress asindicated in parenthesis

The data in Table 14 demonstrate that as the average degree ofoligomerization increased, G′, G″, and the crossover, temperatureincreased, and the shear creep viscosity dramatically increased.

Examples 57-58

In Examples 57-58, using the second portion samples of Examples 55-56,respectively, and each of the copolymers was subjected to 1.73 mW of lowintensity ultraviolet radiation for 20 minutes to effect cure. Therheological characteristics of the copolymers of Examples 57-58 togetherwith those of Example 26 that was prepared using the same reactants butachieving an average degree of oligomerization of 3, are set forth inTable 15.

TABLE 15 Stress at Strain at Swelling Modulus break break in THFExtractables Example (MPa) (MPa) (%) (%) (%) 26 1.51 2.12 180 250  8.457 0.77 1.81 310 407 22.3 58 0.50 0.31 870 dissolved dissolved

The data in Table 15 demonstrate the average degree of oligomerizationincreased, the copolymer was more difficult to cure as indicated by theincreased percent swelling in THF and percent extractables from thecopolymer of Example 26 to the copolymer of Example 57 and the fact thatthe copolymer of Example 58 dissolved in the THF.

Examples 59-64 Examples 59-61

In Example 59, 99.6 parts Polydimethylsiloxane Diamine D, Lot 2,molecular weight 37,800, and 0.4 parts ESACURE™ KB1, a photoinitiator,available from Sartomer Company, Exton, Pa., were fed at a rate of 3.58g/min (0.000189 equivalents amine/min) into the first zone of an 18 mmcounter-rotating twin screw extruder available from LeistritzCorporation, Allendale, N.J.). A mixture of 45.8 parts by weightmethylene dicyclohexylene-4,4′-diisocyanate and 54.2 parts by weightisocyanatoethyl methacrylate was fed at a rate of 0.0266 g/min (0.000186equivalents isocyanate/min) into the fourth zone. The extruder had a40:1 length:diameter ratio and double-start fully intermeshing screwsthroughout the entire length of the barrel, rotating at 100 revolutionsper minute. The temperature profile of the each of the 90 mm long zoneswas: zone 1 to 4-50° C.; zone 5-90° C.; zone 6-170° C., zone 7-180° C.;zone 8−100° C.; and endcap-90° C. Zone seven was vacuun vented. Theresultant extrudate was cooled in air and collected.

In Example 60, a polydimethylsiloxane oligourea segmented copolymer wasprepared as in Example 59, except a mixture of 77.2 parts by weightmethylene dicyclohexylene-4,4′-diisocyanate and 22.8 parts by weightisocyanatoethyl methacrylate was fed at a rate of 0.0252 g/min (0.000185equivalents isocyanate/min) into zone 4.

In Example 61, a polydimethylsiloxane oligourea segmented copolymer wasprepared as in Example 59, except a mixture of 83.5 parts by weightmethylene dicyclohexylene-4,4′-diisocyanate and 16.5 parts by weightisocyanatoethyl methacrylate was fed at a rate of 0.0249 g/min (0.000185equivalents isocyanate/min) into zone 4, zone 6 was at 180° C., and zone8 and endcap were at 150° C.

The copolymers of Examples 59-61 had degrees of polymerization of 2, 5and 7, respectively. The storage modulus, G″, loss modulus, G″,crossover modulus, crossover temperature, and shear creep viscosity at25° C. were determined for Examples 59-61 and, together with those ofExample 49 that was prepared from the same reactants but had an averagedegree of oligomerization of 3, are set forth in Table 16.

TABLE 16 Shear creep Ex- G′ at G″ at Crossover Crossover viscosity atam- 25° C. 25° C. Modulus Temp. 25° C. ple (Pa) (Pa) (Pa) (° C.) (Pa ·s)* 59 0.8 × 10⁴ 0.9 × 10⁴ 1.0 × 10⁴ 18 4.6 × 10⁴ (1 Pa) 49 3.1 × 10⁴2.0 × 10⁴ 1.6 × 10⁴ 65 3.8 × 10⁴ (1 Pa) 60 6.0 × 10⁴ 1.8 × 10⁴ 1.8 × 10⁴104 2.2 × 10⁶ (20 Pa) 61 7.2 × 10⁴ 1.8 × 10⁴ 1.9 × 10⁴ 133 1.8 × 10⁷ (20Pa) *300 seconds shear time; shear stress as marked

The data in Table 16 demonstrate that as the average degree ofoligomerization increased, the shear creep viscosity, storage modulus,crossover modulus and temperature increased.

Examples 62-64

In Examples 62-64, 0.5 parts DAROCUR™ 1173 was added to 100 parts thepolydimethylsiloxane oligourea segmented copolymers of Examples 59-61,respectively, and the copolymers were subjected to 1.73 mW for 20minutes low intensity radiation to cure the copolymers. The copolymer ofExample 64 did not cure. The modulus, stress at break, strain at break,THF swelling calculated by weight, and THF extractables for Examples62-63 and Example 50 are set forth in Table 17.

TABLE 17 Stress at Strain at Swelling modulus break break in THFExtractables Example (MPa) (MPa) (%) (%) (%) 62 0.27 0.71 572 800 16 500.25 0.46 621 1050 26 63 0.2 0.22 868 2200 45

The data in Table 17 demonstrates that as the average degree ofoligomerization increased, the stress at break decreased and the strainat break increased. Also as the average degree of oligomerizationincreased for these high molecular weight polydimethylsiloxane diamines,the percent extractables also increased, indicating diminished curewithno cure occurring at an average degree of oligomerization of 7.

Examples 65-69 Examples 65-67

In Example 65, a polydimethylsiloxane oligourea segmented copolymer wasprepared as in Example 17, except a mixture of 3.25 parts (13.33 mmoles)of tetramethyl-m-xylylene diisocyanate and 1.85 parts (13.33 mmoles) ofvinyl dimethyl azlactone available from S.N.P.E. Chemicals, Princeton,N.J., in 15 parts toluene was added dropwise to a solution of 105.52parts (20.00 mmoles) Polydimethylsiloxane Diamine A molecular weight5280 in 112 parts toluene, and then 15 parts 2-propanol was added.

In Example 66, a polydimethylsiloxane oligourea segmented copolymer wasprepared as in Example 17, except a mixture of 3.25 parts (6.67 mmoles)of tetramethyl-m-xylylene diisocyanate, and 2.68 parts (6.67 mmoles) ofm-isopropenyl-α,α-dimethylbenzyl isocyanate in 15 parts toluene wasadded dropwise to a solution of 105.52 parts (10.00 mmoles) ofPolydimethylsiloxane Diamine A molecular weight 5280 in 112 partstoluene, and then 15 parts 2-propanol was added.

In Example 67, 50 parts of the polydimethylsiloxane oligourea segmentedcopolymer of Example 29 was blended with 50 parts of thepolydimethylsiloxane oligourea segmented copolymer of Example 66.

The average degree of oligomerization of each of the copolymers ofExamples 65-67 was 3. The storage modulus, G′, loss modulus, G″,crossover modulus and crossover temperature were determined for theseExamples. The shear creep viscosity was beyond the limits of the testequipment. The results are set forth in Table 18.

TABLE 18 Crossover Crossover G′ at 25° C. G″ at 25° C. Modulus Temp.Example (Pa) (Pa) (Pa) (° C.) 65 100 × 10⁴ 10 × 10⁴ 20 × 10⁴ 132 66  70× 10⁴ 30 × 10⁴ 20 × 10⁴ 127 67  70 × 10⁴ 20 × 10⁴  8 × 10⁴ 125

The data in Table 18 shows little difference in the copolymers ofExamples 65-67, the differences in the copolymers being only in theterminal groups.

Examples 68 and 69

In Examples 68 and 69, 0.5 part DAROCUR™ 1173 was added to thecopolymers of Examples 65 and 67, respectively, and the copolymer ofExample 68 was subjected to 1.73 mW for 20 minutes ultravioletirradiation while the copolymer of Example 69 was subjected to 1.73 mWfor 60 minutes ultraviolet irradiation to effect free-radicalpolymerization. The copolymner of Example 66, compounded with 0.5 partsDAROCUR™ 1173, did not homopolymerize when irradiated as in Example 69possibly due to steric hindrance. The mechanical properties are setforth in Table 19:

TABLE 19 Stress at Strain at Swelling Modulus break break in THFExtractables Example (MPa) (MPa) (%) (%) (%) 68 6.31 1.75 111 285 9.5 694.03 1.35 120 317 12.7

The data in Table 19 shows that a polydimethylsiloxane oligoureasegmented copolymer incapable of homopolymerization was copolymerizedwith other free radically polymerizable polydimethylsiloxane oligoureasand formed a mixed copolymer.

Examples 70-71 Example 70

In Example 70, a polydiorganosiloxane oligourea segmented polymer wasprepared as in Example 17, except that 100.27 parts (10.4 mmoles)Polydiphenyldimethsiloxane Diamine F, molecular weight 9,620 dissolvedin 94 parts toluene was substituted for Diamine A, and a mixture of 1.82parts (6.95 mmoles) of methylenecyclohexylene-4,4′-diisocyanate and 1.08parts (6.95 mmoles) of isocyanatoethyl methacrylate was used. Thecopolymer of this Example had a degree of oligomerization of 3. Therheological properties were as follows:

Storage modulus 2.8 × 10⁴ Pa Loss modulus 2.8 × 10⁴ Pa Crossover modulus2.8 × 10⁴ Pa Crossover temperature 25° C.

Example 71

In Example 71, 0.5 parts DAROCUR™ 1173 was added to the copolymer ofExample 70 and the copolymer was subjected to 1.73 mW for 20 minutes lowintensity radiation to effect curing. The mnechanical properties,swelling in tetrahydrofuran (THF) and THF extractables were as follows:

Modulus 0.87 MPa Stress at break 1.37 MPa Strain at break 203% Swellingin THF 330% THF extractables 13%

Example 72

In Example 72, a mixture of 99 parts by weight PolydimethylsiloxaneDiamine C, Lot 2, molecular weight 22,300, and 1 part by weight VAZO™64, a thermal initiator available from DuPont Co., was fed into thesixth zone of an 18 mm co-rotating twin screw extruder having a 40:1length:diameter ratio (available from Leistritz Corporation, Allendale,N.J.) at a rate of 6.24 g/min (0.000560 equivalents amine/min). Amixture of 62 parts by weight tetramethyl-m-xylyene diisocyanate and 38parts by weight isocyanatoethyl methacrylate was fed into the sixth zoneat a rate of 0.0645 g/min (0.000486 equivalents isocyanate/min). Thefeed line of this stream was placed close to the screw threads. Theextruder had double-start fully intermeshing screws throughout theentire length of the barrel, rotating at 75 revolutions per minute. Thetemperature for the entire extruder and endcap was set at a 40° C. Thematerial sat at room temperature for 197 days without curing;consequently the VAZO™ 64 initiator became ineffective. More initiatorwas added to the copolymer by kneading in 1 part by weight VAZO™ 64 to100 parts by weight copolymer. The copolymer was cured for 20 minutes inwater at 100° C. The cured copolymer was submerged in tetrahydrofuranfor 24 hours and swelled 930% by volume.

Examples 73-77 Examples 73-75

In Example 73, 50 parts (9.47 mmoles) Polydimethylsiloxane Diamine Amolecular weight 5280, was degassed in a 250 mL round bottom flask and150 parts dichloromethane was added and mixed well. Next, 1.38 parts(6.24 mmoles) aminopropyl triethoxysilane (APS) was added with stirring.Finally, 3.08 parts (12.62 mmoles) tetramethyl-m-xylylene diisocyanatewas added and the solution was mixed for 20 minutes. Thepolydimethylsiloxane oligourea segmented copolymer solution was pouredinto an aluminum tray and stood at room temperature until the solventevaporated.

In Example 74, a polydimethylsiloxane oligourea segmented copolymer wasprepared as in Example 73, except 1.19 parts (6.23 mmoles) ofaminopropyl methyl diethoxysilane (APMS) was substituted for theaminopropyl triethoxysilane.

In Example 75, a polydimethylsiloxane oligourea segmented copolymer wasprepared as in Example 73, except 1.54 parts (6.23 mmoles) ofisocyanatopropyl triethoxysilane (IPS) was substituted for theaminopropyl triethoxysilane, and 1.53 parts (6.27 mmoles) oftetramethyl-m-xylylene diisocyanate was used.

The storage modulus, G′, the loss modulus, G″, and crossover temperaturewere determined for Examples 73-75. The crossover modulus was determinedfor Examples 73 and 75, but was not determinable for Example 74. Theresults are set forth in Table 20.

TABLE 20 Crossover Crossover Capping G′ at 25° C. G″ at 25° C. ModulusTemp. Example agent (Pa) (Pa) (Pa) (° C.) 73 APS 300 × 10⁴ 12 × 10⁴ 25 ×10⁴ 165 74 APMS 300 × 10⁴ 80 × 10⁴ — >170 75 IPS  50 × 10⁴ 20 × 10⁴ 0.4× 10⁴ 150

Examples 76-77

In Examples 76-77, to 100 parts of each of the copolymers of Examples74-75, respectively, was added 1.25 parts trichloroacetic anhydride, andthe solution was subsequently air dried on polyester release liner.These samples were cured for 14 days at 22° C. The cured copolymers ofExamples 76 and 77 were submerged in THF for 24 hours and swelled 340and 290 percent by volume, respectively.

Examples 78-83 Examples 78-80

In Example 78, a mixture of 32.9 parts by weight tetramethyl-m-xylylenediisocyanate, 32.2 parts by weight isocyanatopropyl triethoxysilane,33.8 pairs by weight octyl triethoxy silane, and 1.0 parts by weightdibutyl tin dilaurate was fed into the fifth zone of an 18 mmcounter-rotating twin screw extruder having a 40:1 length:diameter ratio(available from Leistritz Corporation, Allendale, N.J.) at a rate of0.823 g/min (0.00331 equivalents isocyanate/min). The feed line of thisstream was placed close to the screw threads. PolydimethylsiloxaneDiamine A molecular weight 5,280, was added the fifth zone at a rate of8.61 g/min (0.00326 equivalents amine/min). The extruder haddouble-start fully intermeshing screws throughout the entire length ofthe barrel, rotating at 50 revolutions per minute. The temperatureprofile for each of the 90 mm long zones was: zones 1 through 4-30° C.;zone 5-40° C.; zone 6-80° C.; zone 7-90° C.; zone 8-130° C.; andendcap-140° C. Zone seven was vacuum vented to remove entrained air. Theresultant polydimethylsiloxane oligourea segmented copolymer wasextruded and samples were immediately pressed and cured for one week at22° C., 50% relative humidity.

In Example 79, a mixture of 32.9 parts by weight tetramethyl-m-xylylenediisocyanate, 32.2 parts by weight isocyanatopropyl triethoxysilane,33.8 parts by weight octyltriethoxy silane, and 1.0 parts by weightdibutyl tin dilaurate was fed into the fifth zone of an 18 mmcounter-rotating twin screw extruder having a 40:1 length:diameter ratio(available from Leistritz Corporation, Allendale, N.J.) at a rate of0.387 g/min (0.00155 equivalents isocyanate/min). The feed line of thisstream was placed close to the screw threads. PolydimethylsiloxaneDiamine B, molecular weight 10,700, was added the fifth zone at a rateof 8.65 g/min (0.00162 equivalents amine/min). The extruder haddouble-start fully intermeshing screws throughout the entire length ofthe barrel, rotating at 50 revolutions per minute. The temperatureprofile for each of the 90 mm long zones was: zones 1 through 4-30° C.;zone 5-40° C.; zone 6-80° C.; zone 7-90° C.; zone 8 and endcap-120° C.Zone seven was vacuum vented to remove entrained air. The resultantpolydimethylsiloxane oligourea segmented copolymer was extruded andcollected.

In Example 80, a mixture of 32.9 parts by weight tetramethyl-m-xylylenediisocyanate, 32.2 parts by weight isocyanatopropyl triethloxysilane,33.8 parts by weight octyltriethoxy silane, and 1.0 parts by weightdibutyl tin dilaurate was fed into the fifth zone of an 18 mmcounter-rotating twin screw extruder having a 40:1 length:diameter ratio(available friom Leistritz Corporation, Allendale, N.J.) at a rate of0.2171 g/min (0.000872 equivalents isocyanate/min). Tlhe feed line ofthis stream was placed close to the screw threads. PolydimethylsiloxaneDiamine C, molecular weight 22,300, was added the fifth zone at a rateof 8.62 g/min (0.000773 equivalents amine/min). The extruder haddouble-start fully intermeshing screws throughout the entire length ofthe barrel, rotating at 50 revolutions per minute. The temperatureprofile for each of the 90 mm long zones was: zones 1 through 4-30° C.;zone 5-40° C.; zone 6-80° C.; zone 7-90° C.; zone 8 and endcap-120° C.Zone seven was vacuum vented to remove entrained air. The resultantpolymer was extruded and collected.

Each of the copolymers of Examples 78-80 was tested for the storagemodulus, G′, the loss modulus, G″, and crossover temperature withinthree hours of extrusion. The crossover modulus was determined forExamples 79 and 80, but was not determinable for Example 78. The resultsare set forth in Table 22.

TABLE 22 Crossover Crossover G′ at 25° C. G″ at 25° C. Modulus Temp.Example (Pa) (Pa) (Pa) (° C.) 78 24 × 10⁴ 5.0 × 10⁴ — >180 79 10 × 10⁴5.0 × 10⁴ 0.03 × 10⁴ 145 80 10 × 10⁴ 3.0 × 10⁴ 0.2 × 10⁴ 130

Examples 81-83

In Examples 81-83, copolymers prepared in Examples 78-80, respectively,were pressed immediately after extrusion and cured for one week at 22°C., 50% relative humidity. The copolymers were tested for mechanicalproperties and swelling in THF, calculated by volume. The results ofmechanical testing are set forth in Table 23.

TABLE 23 Stress at Strain at Modulus break break Swelling in Example(MPa) (MPa) (%) THF (%) 81 4.82 1.39 110 430 82 1.90 0.81 180 680 831.17 0.89 370 900

As can be seen from the data in Table 23, as the molecular weight of thepolydimethylsiloxane diamine increased, the modulus and stress at breakdecreased and the strain at break increased. Also as the diaminemolecular weight increased, swelling increased indicating lowercrosslink density.

Examples 84-85 Example 84

In Example 84, a mixture of 32.9 parts by weight tetramethyl-m-xylylenediisocyanate, 32.2 parts by weight isocyanatopropyl triethoxysilane,33.8 parts by weight octyl triethoxysilane, and 1.0 parts by weightdibutyl tin dilaurate was fed into the fifth zone of an 18 mmcounter-rotating twin screw extruder having a 40:1 length:diameter ratio(available fron Leistritz Corporation, Allendale, N.J.) at a rate of0.398 g/min (0.00160 equivalents isocyanate/min). The feed line of thisstream was placed close to the screw threads. 75 parts by weightPolydimethylsiloxane Diamine B, molecular weight 10,700, was mixed with25 parts by weight Polydiphenyldimethylsiloxane Diamine F, molecularweight 9,620; the number average molecular weight of this mixture was10,400. This diamine mixture was fed into the fifth zone of the extruderat a rate of 8.72 g/min (0.00168 equivalents amine/min). The extruderhad double-start fully intermeshing screws throughout the entire lengthof the barrel, rotating at 50 revolutions per minute. The temperatureprofile for each of the 90 mm zones was: zones 1 through 4-30° C.; zone5-35° C.; zone 6-80° C.; zone 7-90° C.; zones 8 and endcap-120° C. Zoneseven was vacuum vented to remove entrained air. The resultant polymerwas extruded, collected and tested within three hours for rheologicalproperties. The results were as follows:

Storage modulus 10 × 10⁴ Pa Loss modulus 2.4 × 10⁴ Pa Crossover modulusnone Crossover temperature >180° C.

Example 85

In Example 85, the copolymer prepared in Example 84 was pressedimmediately after extrusion and cured for one week at 22° C., 50%relative humidity. The copolymers were tested for mechanical propertiesand swelling in THF, calculated by volume. The properties were asfollows:

Modulus 1.6 MPa Stress at break 0.77 MPa Strain at break 740 Swelling103%

Examples 86-88

In Example 86, Polydimethylsiloxane Diamine A, Lot 1, molecular weight5280, was injected at a rate of 147 g.min (0.0279 mol/min) into zone 8of a Berstorff 40 mm diameter, 1600 mm length co-rotating extruder.Tetramethyl-m-xylylene diisocyanate was injected into zone 9 at a rateof 7.11 g/min (0.0291 mol/min). The screws rotated at 100 revolutionsper minute. The temperatures of the individual zones were: zones 1through 7 (not used); zone 8-60° C., zone -9-120° C., zone 10 andencap—180° C. The material was extruded into a strand, cooled in aliquid bath, and pelletized.

20 grams of the UV-curable composition of Example 20, 20 grams ofpolydimethylsiloxane polyurea segmented copolymer (as prepared above)and 20 grams toluene/isopropanol 50/50 mixture were agitated until ahomogeneous solution was made. The sample was air dried.

In Example 87, Polydimethylsiloxane Diamine A, Lot 1, molecular weight5280, was injected at a rate of 169 g.min (0.0318 mol/min) into zone 8of a Berstorff 40 mm diameter, 1600 mm length co-rotating extruder.Methylenedicyclohexylene-4,4′-diisocyanate was injected into zone 9 at arate of 8.33 g/min (0.0318 mol/min). The screws rotated at 100revolutions per minute. The temperatures of the individual zones were:zones 1 through 7 (not used); zone 8-60° C., zone-9-120° C., zone 10 andencap-180° C. The material was extruded into a strand, cooled in aliquid bath, and pelletized.

20 grams of the UV-curable composition of Example 20, 20 grams ofpolydimethylsiloxane polyurea segmented copolymer (as prepared above)and 20 grams toluene/isopropanol 50/50 mixture were agitated until ahomogeneous solution was made. The sample was air dried.

In Example 88, a blend UV-curable polydiorganosiloxane oligoureasegmented copolymer and non-curable polydiorganosiloxane polyureasegmented copolymer was made analogously as in Example 86, except 20grams of UV-curable composition of Example 20 was substituted with 20grams polydiorganosiloxane oligourea segmented copolymer of Example 29.

The storage modulus, G′, loss modulus, G″ (at 25° C.), crossovermodulus, and crossover temperature were determined for the uncuredblends of UV curable polydiorganosiloxane oligourea segmented copolymerswith polydiorganosiloxane polyurea segmented copolymers of Examples86-88. The results are set forth in Table 24.

TABLE 24 Ex. 86 Ex 87 Ex. 88 G′ 7.8 × 10⁵ Pa 1.4 × 10⁵Pa 3.0 × 10⁵ Pa G″1.2 × 10⁵ Pa 5.8 × 10⁴ Pa 3.0 × 10⁴ Pa crossover modulus 2.1 × 10⁵ Pa8.9 × 10² Pa undeterminable crossover temperaturer 112° C. 142° C. above170° C.

Dried portions of the samples of Examples 86, 87, and 88 were pressed,cured and tested for mechanical properties, swellability in the THF, andextractability in the THF, as described in Example 23. The results areset forth in Table 25

TABLE 25 Ex. 86 Ex. 87 Ex. 88 Modulus [MPa] 3.44 1.18 4.67 Stress atbreak [MPa] 1.71 1.50 1.69 Strain at break 230% 290% 200% Swellability1700% 1200% 1300% Extractables 54% 37% 42%

Example 89

In Example 89, a blend of equal parts of the compositions of Example 20,Example 43, Example 44, and Example 59 was made in a 50/50toluene/isopropanol mixture, and subsequently dried in air.

The storage modulus, G′, loss modulus, G″ (at 25° C.), crossovermodulus, and crossover temperature were determined for the uncuredportion of the sample. The results are set forth in Table 24.

TABLE 26 G′ 8.0 × 10³ Pa G″ 1.0 × 10⁴ Pa crossover modulus 1.7 × 10⁴ Pacrossover temperature 12° C.

A portion of the sample was pressed, cured, and characterized as inExample 86, and the results are presented below.

Ex. 89 Modulus [MPa] 0.55 Stress at break [MPa] 1.38 Strain at break308% Swellability 800% Extractables 10%

Example 90

In Example 90, 0.30 grams , 1,12-diaminedodecane (Available from AldrichChemical), and 100.0 grams Polydimethylsiloxane Diamine D, Lot 2 wasdissolved in 100 grams of a 50/50 toluene/isopropanol mixture. To thesolution was added dropwise a mixture of 0.46 gramsisocyanatoethylmethacrylate and 0.72 grams tetramethyl-m-xylylenediisocyanate in 20 grams toluene/isopropanol (50/50) mixture. To thesolution was added 1.0 gram DAROCUR™ 1173, and the resulting mixture wasdried in air to form a white, viscous fluid. One part of the uncuredpolymer was used to test rheological properties as described in Example86, and the results are presented below.

Storage Modulus at 25° C. 1.1 × 10¹ Pa Loss Modulus at 25° C. 2.4 × 10²Pa Crossover Modulus undetermined Crossover Temperature below −30° C.

A portion of the dried polymer was pressed, cured, and tested asdescribed in Example 86

Modulus [MPa] 0.13 Stress at break [MPa] 0.21 Strain at break 377%Swelling in THF 1210% Extractables 40.0%

Example 91

In Example 91, 1.9 grams 1,12-diaminedodecane, and 100.0 gramsPolydimethylsiloxane Diamine A, lot 1 was dissolved in 100 grams of a50/50 toluene/isopropanol mixture. To the solution was added dropwise amixture of 2.94 grams isocyanatoethylmethacrylate and 4.62 gramstetramethyl-m-xylylene diisocyanate in 20 grams of a toluene/isopropanol50/50 mixture. To the solution was added 1.0 gram DAROCUR™ 1173, and theresulting mixture was dried in air to form a hazy, semisolid. One partof the uncured polymer was used to test rheological properties asdescribed in Example 86.

Storage Modulus at 25° C. 2.0 × 10⁵ Pa Loss Modulus at 25° C. 9.3 × 10⁴Pa Crossover Modulus 8.3 × 10⁴ Pa Crossover Temperature 40° C.

A portion of the dried polymer was pressed, cured, and tested asdescribed in Example 86.

Modulus [MPa] 6.26 Stress at break [MPa] 1.73 Strain at break 100%Swelling in THF 317% Extractables 13.3%

Example 92

In Example 92, 0.96 grams Polyamine IH1000 (available from Air Productsand Chemicals, Inc.), and 100.0 grams Polydimethylsiloxane Diamine D,Lot 2 was dissolved in 100 grams of a toluene/isopropanol 50/50 mixture.To the solution was added dropwise a mixture of 0.46 gramsisocyanatoethylmethacrylate and 0.72 grams tetramethyl-m-xylylenediisocyanate in 20 grams toluene/isopropanol (50/50) mixture. To thesolution was added 1.0 gram DAROCUR™ 1173, and the resulting mixture wasdried in air to form white, very viscous fluid. One part of the polymerwas used to test rheological properties as described in Example 86.

Storage Modulus at 25 C. 1.3 × 10² Pa Loss Modulus at 25 C. 9.8 × 10² PaCrossover Modulus 1.0 × 10⁴ Pa Crossover Temperature −30° C.

A portion of the dried polymer was pressed, cured, and tested asdescribed in Example 86.

Modulus [MPa] 0.21 Stress at break [MPa] 0.62 Strain at break 516%Swelling in THF 1027% Extractables 20.3%

Example 93

In Example 93, 5.24 grams tetramethyl-m-xylylene diisocyanate wascharged to a 500 ml flask in 10 milliliters of dichloromethane. To thiswas added 31.7 grams of Jeffamine D-2000, and the sample was well mixed.Next was added a solution of 61.4 grams of PDMS Diamine A, Lot 1 in 40ml dichloromethane. Next, 1.66 grams isocyanatoethylmethacrylate wasadded and the solution was mixed for 15 minutes, followed by theaddition of 1.1 grams DAROCUR™ 1173. The mixture was allowed to dry on aliner in the dark to form blueish, somewhat inhomogeneous semisolid.

One part of the uncured polymer was used to test rheological propertiesas described in Example 86.

Storage Modulus at 25° C. 1.6 × 10⁵ Pa Loss Modulus at 25° C. 6.8 × 10⁴Pa Crossover Modulus 5.5 × 10⁴ Pa Crossover Temperature 55° C.

Dried polymer was pressed at 90° C. into approx. 1 millimeter filmbetween two liners and exposed to low intensity UV lights for 20minutes, and tested as described in Example 86.

Modulus [MPa] 4.38 Stress at break [MP] 1.04 Strain at break 218%Swelling in THF 430% Extractables 14.1%

Example 94

In Example 94, a Berstorff 25 mm diameter corotating twin screw extruderhaving a 29.5:1 length diameter ratio was used with a dual injectionport at zone 1 and a single injection port at both zones 3 and 4. Doublestart fully intermeshing screws, rotating at 125 revolutions per minute,were used throughout the entire length of the barrel with 2 sets of 25mm length kneading blocks located at the end of zone 5. The temperatureprofile for each of the zones was: zone 1-30° C.; zone 2-75° C.; zone3-100° C.; zone 4-125° C.; zone 5-150° C.; zone 6-175° C.; endcap-190°C.; meltpump-200° C.; and necktube-230° C. The feedstock reagents weremaintained under a nitrogen atmosphere. A blend of 98 parts by weightPolydimethylsiloxane Diamine A, Lot 2, molecular weight 5310, and 2parts by weight Polydimethylsiloxane Monoamine C, molecular weight12,121 was injected at a rate of 15.13 g/min (0.00280 mol/min) into thefirst part of zone 1 and methylenedicyclohexylene-4,4′-diisocyanate(DESMODUR W, obtained from Miles Laboratory) was injected at a rate of29.59 g/min (0.113 mol/min) into the second part of zone 1. Jeffamine™D-400 polyoxypropylenediamine (obtained from Huntsman Corporation,molecular weight 466 g/mol for Lot #5C710) was injected at a rate of21.19 g/min (0.0455 mol/min) into zone 3. Dytek A™(2-methyl-1,5-pentanediamine obtained from DuPont, molecular weight of116 g/mol for Lot #SC950419J01)) was injected at zone 4 at a rate of8.33 g/min (0.0718 mol/min). The resultant polydimethylsiloxaneoligourea segmented copolymer of NCO:NH₂ ratio 0.94:1, was extruded as a2.5 mm diameter strand into a Fluorinert™ dryice bath and pelletized toafford a product with a bimodal distribution by GPC with an overallM_(n)=1.1×10⁵.

Example 95

In Example 95, a Berstorff 25 mm diameter corotating twin screw extruderwas used as in Example 94 with the following modifications. The screw,operating at 100 revolutions per minute, was constructed with doublestart fully intermeshing screws used in combination with partiallyintermeshing screws with one set of 25 mm length kneading blocks locatedat the start of zone 4 and three sets located at the end of zone 5. Thetemperature profile for each of the zones was: zone 1-30° C.; zone 2-75°C.; zone 3-100° C.; zone 4-125° C.; zone 5-150° C.; zone 6-175° C.;endcap and meltpump-175° C. and necklube—190° C. The feedstock reagentswere maintained under a nitrogen atmosphere. PolydimethylsiloxaneDiamine A, Lot 1, 5280 molecular weight was fed at a rate of 4.85 g/min(0.000919 mol/min) into the first part of zone 1. A blend of 20 parts byweight phenyl isocyanate (obtained from Matheson Coleman and Bell) and80 parts by weight methylenedicyclohexylene-1,4′-diisocyanate (DESMODURW, obtained from Miles Laboratory Lot #D233-4-0751) was fed at a rate of12.81 g/min (0.0499 mol/min) into the second part of zone 1. Jeffamine™D-400 polyoxypropylenediamine (obtained from Huntsman Corporation,titrated molecular weight 452 g/mol for Lot #CP5131) was injected at19.45 g/min (0.0430 mol/min) into zone 3. And Dytek A™(2-methyl-1,5-pentanediamine obtained from DuPont, titrated molecularweight 117 g/mol for Lot #SC94030211) was injected at zone 4 at a rateof 0.689 g/min (0.00589 mol/min). The resultant polydimethylsiloxaneoligourea segmented copolymer of NCO:NH₂ ratio 1.00:1, was extruded as astrand to yield a product with M_(n)=3.3×10⁴by GPC analysis.

The various modifications and alterations of this invention will beapparent to those skilled in the art without departing from the scopeand spirit of this invention and this invention should not be restrictedto that set forth herein for illustrative purposes.

What is claimed is:
 1. Polydiorganosiloxane oligourea segmentedcopolymers comprising (i) a pair of soft polydiorganosiloxane amineresidue units, wherein the polydiorganosiloxane amine residue unit is apolydiorganosiloxane amine minus all —NDH groups with D selected fromhydrogen, alkyl radicals having 1 to 10 carbon atoms, phenyl and aradical that completes a ring structure to form a heterocycle havingabout 6 to 20 carbon atoms, (ii) a single hard polyisocyanate residueunit, wherein the polyisocyanate residue unit is a polyisocyanate minusthe —NCO groups, (iii) urea linkages connecting the isocyanate residueunit and the polydiorganosiloxane amine residue units, and (iv) terminalgroups that are not reactive under moisture curing or free radicalcuring conditions and are not a reactive amine or a reactive isocyanate.2. A polydiorganosiloxane oligourea segmented copolymer according toclaim 1 represented by the formula:

wherein each Z is a polyvalent radical selected from (i) aryleneradicals and aralkylene radicals having from about 6 to 20 carbon atoms,and (ii) alkylene and cycloalkylene radicals having from about 6 to 20carbon atoms; each R is a moiety independently selected from (i)substituted and unsubstituted alkyl moieties, (ii) substituted andunsubstituted vinyl radicals and higher alkenyl radicals, (iii)substituted and unsubstituted cycloalkyl moieties having about 6 to 12carbon atoms, (iv) substituted and unsubstituted aryl moieties, (v)perfluoroalkyl groups, (vi) fluorine-containing groups, and (vii)perfluoroether-containing groups; each Y is a polyvalent moietyindependently selected from (i) alkylene radicals having 1 to 10 carbonatoms, and (ii) aralkylene radicals and arylene radicals having 6 to 20carbon atom; each D is independently selected from hydrogen, alkylradicals having 1 to 10 carbon atoms, phenyl, and radicals that completea ring structure including B or Y to form a heterocycle having about 6to 20 carbon atoms; each A is independently —B—, or—YSi(R)₂(OSi(R)₂)_(p)Y- or mixtures thereof; B is a polyvalent radicalselected from the group consisting of alkylene, aralkylene,cycloalkylene, phenylene, polyalkylene oxide and copolymers thereof, andmixtures thereof, e and b are o and n and d are 1; q is about 10 orlarger; and each X is independently: (a) a monovalent alkyl, substitutedalkyl, aryl or substituted aryl moiety that is not reactive undermoisture curing or free radical curing conditions; or (b) a moietyrepresented by

wherein D is as defined as above, and K is a monovalent alkyl,substituted alkyl, aryl or substituted aryl moiety that is not reactiveunder moisture curing or free radical curing conditions.
 3. Thepolydiorganosiloxane diamine oligourea segmented copolymer according toclaim 2, wherein R is a moiety independently selected from (i)substituted and unsubstituted alkyl moieties having 1 to 12 carbonatoms, (ii) radicals represented by the formula —R²(CH₂)_(a)CH=CH₂;wherein R² is —(CH₂)_(b)- or —(CH₂)_(c)CH=CH-; a is 1,2 or 3; b is 0, 3or 6; and c is 3, 4 or 5, (iii) cycloalkyl moieties wherein the cycloportion of the moiety has 6 to 12 carbon atoms and is substituted withan alkyl, fluoroalkyl or vinyl group, and (iv) substituted andunsubstituted aryl moieties having 6 to 20 carbon atoms.
 4. Apolydiorganosiloxane oligourea copolymer according to claim 2, whereinat least 50% of the R moieties are methyl radicals with the balancebeing monovalent alkyl or substituted alkyl radicals, alkenyleneradicals, phenyl radicals, or substituted phenyl radicals.
 5. Thepolydiorganosiloxane diamine oligourea segmented copolymer according toclaim 3, wherein at least one R is a substituted alkyl moiety orsubstituted aryl moiety and further wherein (i) when the alkyl moiety issubstituted the alkyl moiety is substituted with a trifluoroalkyl orvinyl group and (ii) when the aryl moiety is substituted the aryl moietyis substituted with an alkyl, cycloalkyl, fluoroalkyl or vinyl group. 6.A polydiorganosiloxane oligourea segmented copolymer according to claim2, wherein X is a monovalent unsubstituted alkyl moiety having about 1to 20 carbon atoms.
 7. A polydiorganosiloxane oligourea segmentedcopolymer according to claim 2, wherein X is a monovalent unsubstitutedaryl moiety having about 6 to 20 carbon atoms.
 8. A polydiorganosiloxaneoligourea segmented copolymer according to claim 2, wherein X is amonovalent alkyl moiety substituted with trifluoroalkyl groups.
 9. Apolydiorganosiloxane oligourea segmented copolymer according to claim 2,wherein X is an aryl moiety substituted with alkyl, aryl, or substitutedaryl groups.
 10. A polydiorganosiloxane oligourea segmented copolymeraccording to claim 2, wherein K is monovalent unsubstituted alkylmoiety.
 11. A polydiorganosiloxane oligourea segmented copolymeraccording to claim 2, wherein K is a monovalent unsubstituted arylmoiety.
 12. A polydiorganosioxane oligourea segmented copolymeraccording to claim 2, wherein K is a monovalent substituted alkylmoiety.
 13. A polydiorganosiloxane oligourea segmented copolymeraccording to claim 2, wherein K is a substituted aryl moiety.
 14. Apolydiorganosiloxane oligourea copolymer according to claim 12 wherein Zis selected from the group consisting of 2,6-tolylene,4,4′-methylenediphenylene, 3,3′- dimethoxy-4,4′-biphenylene,tetramethyl-m-xylylene, 4,4′-methylenedicyclohexylene,3,5,5-trimethyl-3-methylenecyclohexylene, 2,2,4-trimethylhexylene,1,6-hexamethylene, 1,4-cyclohexylene, and mixtures thereof.
 15. Apolydiorganosiloxane oligourea copolymer according to claim 14 wherein Zis tetramethyl-m-xylylene.
 16. Poyldiorganosiloxane oligourea segmentedcopolymer comprising the reaction product of: (a) a polyisocyanate; and(b) a polydiorganosiloxane monoamine having a first terminal portionreactive with an isocyanate and a second terminal portion that is notreactive under moisture curing or free radical curing conditions and isnot a reactive amine or a reactive isocyanate.
 17. A process forpreparing polydiorganosiloxane oligourea segmented copolymers comprisingthe steps of: (a) providing reactants, wherein the reactants comprise(i) a polyisocyanate, (ii) a polydiorganosiloxane monoamine having afirst terminal portion that is an amine and a second terminal portionthat is not reactive under moisture curing or free radical curingconditions and is not a reactive amine or a reactive isocyanate, and(iii) solvent, to a reactor; (b) mixing the reactants in the reactor;(c) allowing the reactants to react to form a polydiorganosiloxaneoligourea segmented copolymer having (i) a single hard polisocyanateresidue unit, wherein the polyisocyanate residue unit is thepolyisocyanate minus the —NCO groups, (ii) a pair of softpolydiorganosiloxane amine residue units, wherein thepolydiorganosiloxane amine residue units are the polydiorganosiloxanemonamine minus the —NDH group with D selected from hydrogen, alkylradicals having 1 to 10 carbon atoms, phenyl and a radical thatcompletes a ring structure to form a heterocycle having about 6 to 20carbon atoms, and (iii) urea linkage connecting the isocyanate residueunit and the polydiorganosiloxane amine residue units; and (d) conveyingthe oligomer from the reactor.
 18. An essentially solventless processfor preparing polydiorganosiloxane oligourea segmented copolymerscomprising the steps of: (a) continuously providing reactants to areactor under substantially solventless conditions, wherein thereactants comprise (i) a polyisocyanate, and (ii) a polydiorganosiloxanemonoamine having a first terminal portion that is an amine and a secondterminal portion that is not reactive under moisture curing or freeradical curing conditions and is not a reactive amine or a reactiveisocyanate; (b) mixing the reactants in the reactor under thesubstantially solventless conditions; (c) allowing the reactions toreact to form a polydiorganosiloxane oligourea segmented copolymerhaving (i) a single hard polyisocyanate residue unit, wherein thepolyisocyanate residue unit is the polyisocyanate minus the —NCO groups,(ii) a pair of soft polydiorganosiloxane amine residue units, whereinthe polydiorganosiloxane amine residue units are thepolydiorganosiloxane monoamine minus the —NDH group with D selected fromhydrogen, alkyl radicals having 1 to 10 carbon atoms, phenyl and aradical that completes a ring structure to form a heterocycle havingabout 6 to 20 carbon atoms, and (iii) urea linkage connecting theisocyanate residue unit and the polydiorganosiloxane amine residueunits; and (d) conveying the oligomer from the reactor. 19.Polydiorganosiloxane oligourea segmented copolymers comprising (i) softpolydiorganosiloxane amine residue units, wherein thepolydiorganosiloxane amine residue units are the polydiorganosiloxaneamine minus all —NDH groups with D selected from hydrogen, alkylradicals having 1 to 10 carbon atoms, phenyl and a radical thatcompletes a ring structure to form a heterocycle having about 6 to 20carbon atoms, (ii) Hard polyisocyanate residue units, wherein thepolyisocyanate residue units are the polyisocyanate minus the —NCOgroups, (iii) moisture curable monoisocyanate residue terminal units,wherein the moisture curable monoisocyanate residue terminal units arethe monoisocyanate minus the —NCO group and the moisture curablemonoisocyanate residue terminal units are selected from the groupconsisting of propyl trimethoxysilane, propyl triethoxysilane, propyldimethoxy (methylethylketoximino)silane, propyl diethoxy(methylethylketoximino)silane, propyl monomethoxydi(methylethylketoximino)silane, propyl monoethoxydi(methylethylketoximino) silane, and propyltri(methylethylketoximino)silane, and (iv) urea linkages connecting theisocyanate residue units, the polydiorganosiloxane amine residue unitsand the moisture curable terminal groups.
 20. A polydiorganosiloxaneoligourea segmented copolymer according to claim 19 represented by theformula:

wherein each Z is a polyvalent radical selected from (i) aryleneradicals and aralkylene radicals having from about 6 to 20 carbon atoms,and (ii) alkylene and cycloaklylene radicals having from about 6 to 20carbon atoms; each R is a moiety independently selected from (i)substituted and unsubstituted alkyl moieties, (ii) substituted andunsubstituted vinyl radicals and higher alkenyl radicals, (iii)substituted and unsubstituted cycloalkyl moieties having about 6 to 12carbon atoms, (iv) substituted and unsubstituted aryl moieties, (v)perfluoroalkyl groups, (vi) fluorine-containing groups, and (vii)perfluorother-containing groups; each Y is a polyvalent moietyindependently selected from (i) alkylene radicals having 1 to 10 carbonatoms, and (ii) aralkylene radicals and arylene radicals having 6 to 20carbon atoms; each D is independently selected from hydrogen, alkylradicals having 1 to 10 carbon atoms, phenyl, and radicals that completea ring structure including B or Y to form a heterocycle having about 6to 20 carbon atoms; each A is independently —B—, or—YSi(R)₂(OSi(R)₂)_(p)Y- or mixtures thereof; B is a polyvalent radicalselected from the group consisting of alkylene, aralyklene,cycloalkylene, phenylene, polyalkylene oxide and copolymers thereof, andmixtures thereof, m is a number that is 0 to about 8; b, e, d and n are0 or 1, with the provisos the b+d=1 and e+n=1; p is about 10 or larger;q is about 10 or larger; and t is a number which is 0 to about 8; andeach X is independently a moiety represented by

wherein D is as defined as above, and K is a moisture curable groupselected from propyl trimethoxysilane, propyl triethoxysilane, propyldimethoxy (methylethylketoximino)silane, propyl diethoxy(methylethylketoximino)silane, propyl monomethoxydi(methylethylketoximino)silane, propyl monoethoxydi(methylethylketoximino) silane, and propyltri(methylethylketoximino)silane.
 21. The polydiorganosiloxane diamineoligourea segmented copolymer, according to claim 20, wherein R is amoiety independently selected from (i) substituted and unsubstitutedalkyl moieties having 1 to 12 carbon atoms, (ii) radicals represented bythe formula —R²(CH₂)_(a)CH=CH₂ ; wherein R² is —(CH₂)_(b)- or—(CH₂)_(c)CH=CH-; a is 1, 2 or 3; b is 0, 3 or 6; and c is 3, 4 or 5,(iii) cycloalkyl moieties wherein the cyclo portion of the moiety has 6to 12 carbon atoms and is substituted with an alkyl, fluoroalkyl orvinyl group, and (iv) substituted and unsubstituted aryl moieties having6 to 20 carbon atoms.
 22. The polydiorganosiloxane diamine oligoureasegmented copolymer, according to claim 21 wherein at least one R is asubstituted alkyl moiety or substituted aryl moiety and further wherein(i) when the alkyl moiety is substituted the alkyl moiety is substitutedwith a trifluoroalkyl or vinyl group and (ii) when the aryl moiety issubstituted the aryl moiety is substituted with an alkyl, cycloalkyl,fluoroalkyl or vinyl group.
 23. A polydiorganosiloxane oligoureacopolymer according to claim 20 wherein at least 50% of the R moietiesare methyl radicals with the balance being monovalent alkyl orsubstituted alkyl radicals, alkenylene radicals, phenyl radicals, orsubstituted phenyl radicals.
 24. A polydiorganosiloxane oligoureacopolymer according to claim 20 wherein Z is selected from the groupconsisting of 2,6-tolylene, 4,4′-methylenediphenylene, 3,3′-dimethoxy-4,4′-biphenylene, tetramethyl-m-xylylene,4,4′-methylenedicyclohexylene, 3,5,5-trimethyl-3-methylenecyclohexylene,2,2,4-trimethylhexylene, 1,6-hexamethylene, 1,4-cyclohexylene, andmixtures thereof.
 25. A polydiorganosiloxane oligourea copolymeraccording to claim 24 wherein Z is tetramethyl-m-xylylene. 26.Polydiorganosiloxane oligurea segmented copolymer comprising thereaction product of: (a) at least one polyisocyanate; (b) at least onepolydiorganosiloxane diamine; and (c) at least one non-siloxanecontaining endcapping agent wherein the endcapping agent has a firstterminal portion reactive with an amine, and a second terminal portionthat can react under moisture-cure conditions.
 27. A process forpreparing polydiorganosiloxane oligourea segmented copolymers comprisingthe steps of: (a) providing reactants to a reactor, wherein thereactants comprise (i) at least one polyisocyanate, (ii) at least onepolydiorganosiloxane diamine, and (iii) at least one non-siloxanecontaining endcapping agent wherein the endcapping agent has a firstterminal portion of an —NCO group, and a second terminal portion thatcan react under moisture-cure conditions selected from the groupconsisting of propyl trimethoxysilane, propy triethoxysilane, propyldimethoxy (methylethylketoximino)silane, propyl diethoxy(methylethylketoximino)silane, propyl monomethoxydi(methylethylketoximino)silane, propyl monoethoxydi(methylethylketoximino) silane, and propyltri(methylthylketoximino)silane, and (iv) solvent; (b) mixing thereactants in the reactor; (c) allowing the reactants to react to form apolydiorganosiloxane oligourea segmented copolymer having (i) softpolydiorganosiloxane amine residue units, wherein thepolydiorganosiloxane amine residue units are the polydiorganosiloxaneamine minus all —NDH groups with D selected from hydrogen, alkylradicals having 1 to 10 carbon atoms, phenyl and a radical thatcompletes a ring structure to form a heterocycle having about 6 to 20carbon atoms, (ii) hard polyisocyanate residue units, wherein thepolyisocyanate residue units are the polysisocyanate minus the —NCOgroups, (iii) endcapping agent residue units wherein the endcappingagent residue units are the endcapping agent minus the —NCO group, and(iv) urea linkages connecting the isocyanate residue units, thepolydiorganosiloxane amine residue units and the endcapping agentresidue units; and (d) conveying the oligomer from the reactor.
 28. Anessentially solventless process for preparing polydiorganosiloxaneoligourea segmented copolymers comprising the steps of: (a) continuouslyproviding reactants to a reactor under substantially solventlessconditions, wherein the reactants comprise (i) at least onepolyisocyanate, (ii) at least one polydiorganosiloxane diamine, and(iii) at least one non-siloxane containing endcapping agent wherein theendcapping agent has a first terminal portion of an —NCO group, and asecond terminal portion that can react under moisture-cure conditions;(b) mixing the reactants in the reactor under the substantiallysolventless conditions; (c) allowing the reactants to react to form apolydiorganosiloxane oligourea segmented copolymer having (i) softpolydiorganosiloxane amine residue units, wherein thepolydiorganosiloxane amine residue units are the polydiorganosiloxaneamine minus all —NDH groups with D selected from hydrogen, alkylradicals having 1 to 10 carbon atoms, phenyl and a radical thatcompletes a ring structure to form a heterocycle having about 6 to 20carbon atoms, (ii) hard polyisocyanate residue units, wherein thepolyisocyanate residue units are the polyisocyanate minus the —NCOgroups, (iii) endcapping agent residue units wherein the endcappingagent residue units are the endcapping agent minus the —NCO group, and(iv) urea linkages connecting the isocyanate residue units, thepolydiorganosiloxane amine residue units and the endcapping agentresidue units; and (d) conveying the oligomer from the reactor. 29.Polydiorganosiloxane oligourea segmented copolymers comprising (i) softpolydiorganosiloxane amine residue units, wherein thepolydiorganosiloxane amine residue units are a polydiorganosiloxaneamine minus all —NDH groups with D selected from hydrogen, alkylradicals having 1 to 10 carbon atoms, phenyl and a radical thatcompletes a ring structure to form a heterocycle having about 6 to 20carbon atoms, (ii) hard polyisocyanate residue units, wherein thepolyisocyanate residue units are a polyisocyanate minus the —NCO groups,(iii) monoamine residue terminal units having an endcapping group,wherein the monoamine residue terminal units are a monamine minus the—NDH group with D selected from hydrogen, alkyl radicals having 1 to 10carbon atoms, phenyl and a radical that completes a ring structure toform a heterocycle having about 6 to 20 carbon atoms, and (iv) urealinkage connecting the isocyanate residue units, thepolydiorganosiloxane amine residue units and the monoamine residueterminal units, wherein the monamine residue terminal units areconnected through the —NDH group on the monoamine.
 30. Apolydiorganosiloxane oligourea segmented copolymer according to claim 29represented by the formula:

wherein each Z is a polyvalent radical selected from (i) aryleneradicals and aralkylene radicals having from about 6 to 20 carbon atoms,and (ii) alkylene and cycloalkylene radicals having from about 6 to 20carbon atoms; each R is a moiety independently selected from (i)substituted and unsubstituted alkyl moieties, (ii) substituted andunsubstituted vinyl radicals and higher alkenyl radicals, (iii)substituted and unsubstituted cycloalkyl moieties having about 6 to 12carbon atoms, (iv) substituted and unsubstuted aryl moieties, (v)perfluoroalkyl groups, (vi) fluorine-containing groups, and (vii)perfluoroether-containing groups; each Y is a polyvalent moietyindependently selected from (i) alkylene radicals having 1 to 10 carbonatoms, and (ii) aralkylene radicals and arylene radicals having 6 to 20carbon atoms; each D is independently selected from hydrogen, alkylradicals having 1 to 10 carbon atoms, phenyl, and radicals that completea ring structure including B or Y to form a heterocycle having about 6to 20 carbon atoms; each A is independently —B—, or—YSi(R)₂(OSi(R)₂)_(p)Y- or mixtures thereof; B is a polyvalent radicalselected from the group consisting of alkylene, aralkylene,cycloclkylene, phenylene, polyalkylene oxide and copolymers thereof, andmixtures thereof, m is a number that is 0 to about 8; b, e, d and n are0 or 1, with the provisos that b+d=1 and e+n=1; p is about 10 or larger;q is about 10 or larger; and t is a number which is 0 to about 8; andeach X is independently a moiety represented by

where each of Z and D are as defined as above, and K is independently(i) a moiety that is not reactive under moisture curing or free radicalcuring conditions selected from the group consisting of alkyl,substituted alkyl, aryl, and substituted aryl, (ii) a free radicallycurable end group, or (iii) a moisture curable group.
 31. Thepolydiorganosiloxane diamine oligourea segmented copolymer, according toclaim 30, wherein R is a moiety independently selected from (i)substituted and unsubstituted alkyl moieties having 1 to 12 carbonatoms, (ii) radicals represented by the formula —R²(CH₂)_(a)CH=CH₂;wherein R² is —(CH₂)_(b)- or —(CH₂)_(c)CH=CH-; a is 1, 2 or 3; b is 0, 3or 6; and c is 3, 4 or 5, (iii) cycloalkyl moieties wherein the cycloportion of the moiety has 6 to 12 carbon atoms and is substituted withan alkyl, fluoroalkyl or vinyl group, and (iv) substituted andunsubstituted aryl moieties having 6 to 20 carbon atoms.
 32. Thepolydioranosiloxane diamine oligourea segmented copolymer, according toclaim 31 wherein at least one R is a substituted alkyl moiety orsubstituted aryl moiety and further wherein (i) when the alkyl moiety issubstituted the alkyl moiety is substituted with a trifluoroalkyl orvinly group and (ii) when the aryl moiety is substituted the aryl moeityis substituted with an alkyl, cycloalkyl, fluoroalkyl or vinyl group.33. A polydiorganosiloxane oligourea copolymer according to claim 30wherein at least 50% of the R moieties are methyl radicals with thebalance being monovalent alkyl or substituted alkyl radicals, alkeyleneradicals, phenyl radicals, or substituted pheyl radicals.
 34. Apolydiorganosiloxane oligourea copolymer according to claim 30 wherein Zis selected from the group consisting of 2,6tolylene,4,4′-methylenediphenylene, 3,3′dimethoxy-4,4′-biphenylene,tetramethyl-m-xylylene, 4,4′-methylenedicyclohexylene,3,5,5-trimethyl-3-methylenecyclohexylene, 2,2,4-trimethylhexylene,1,6-hexamethylene, 1,4-cyclohexylene, and mixtures thereof.
 35. Apolydiorganosiloxane oligourea copolymer according to claim 34 wherein Zis tetramethyl-m-xylylene.
 36. A polydiorganosiloxane oligoureacopolymer according to claim 30 wherein K is a free radically curablegroup selected from the group consisting of acrylate, methacrylate,acrylamido, methacrylamido and vinyl.
 37. A polydiorganosiloxaneoligourea copolymer according to claim 30 wherein K is a moisturecurable group selected from the group consisting of propyltrimethoxysilane, propyl triethoxysilane, propyl methyldimethoxysilane,propyl methyldiethoxysilane, propyl dimethoxy(methylethylketoximino)silane, propyl diethoxy(methylethylketoximino)silane, propylmonomethoxydi(methylethylketoximino)silane, propylmonoethoxydi(methylethylketoximino)silane, and propyltri(methylethylketoximino)silane, mixtures thereof and partialhydrolyzates thereof.
 38. Polydiorganosiloxane oligourea segmentedcopolymer comprising the reaction product of: (a) at least onepolyisocyanate; (b) at least one polydiorganosiloxane diamine; and (c)at least one non-siloxane containing endcapping agent wherein theendcapping agent has a first terminal portion reactive with anisocyanate, and a second terminal portion selected from the groupconsisting of (i) a moiety that is not reactive under moisture curing orfree radical curing conditions selected from the group consisting ofalkyl, substituted alkyl, aryl, and substituted aryl, (ii) a freeradically curable end group, or (iii) a moisture curable group selectedfrom the group consisting of propyl trimethoxysilane, propyltriethoxysilane, propyl methyldimethoxysilane, propylmethyldiethoxysilane, propyl dimethoxy (methylethylketoximino)silane,propyl diethoxy (methylethylketoximino)silane, propylmonomethoxydi(methylethylketoximino)silane, propylmonoethoxydi(methylethylketoximino)silane, and propyltri(methylethylketoximono)silane, mixtures thereof and partialhydrolyzates thereof.
 39. A process for preparing polydiorganosiloxaneoligourea segmented copolymers comprising the steps of: (a) providingreactants to a reactor, wherein the reactants comprise (i) at least onepolyisocyanate, (ii) at least one polydiorganosiloxane diamine, and(iii) at least one non-siloxane containing endcapping agent wherein theendcapping agent has a first terminal portion reactive with anisocyanate, and a second terminal portion selected from the groupconsisting of (A) a moiety that is not reactive under moisture curing orfree radical curing conditions selected from the group consisting oralkyl, substituted alkyl, aryl, and substituted aryl (B) a freeradically curable end group, or (C) a moisture curable group selectedfrom the group consisting of propyl trimethoxysilane, propyltriethoxysilane, propyl methyldimethoxysilane, propylmethyldiethoxysilane, propyl dimethoxy (methylethylketoximino)silane,propyl diethoxy (methylethylketoximino)silane, propylmonomethoxydi(methylethylketoximino)silane, propylmonoethoxydi(methylethylketoximino)silane, and propyltri(methylethylketoximino)silane mixtures thereof and partialhydrolyzates thereof, and (iv) solvent; (b) mixing the reactants in thereactor; allowing the reactants to react to form a polydioganosiloxaneoligourea segmented copolymer having (i) soft polydiorganosiloxane amineresidue units, wherein the polydiorganosiloxane amine residue units area polydiorganosiloxane amine minus all —NDH groups with D selected fromhydrogen, alkyl radicals having 1 to 10 carbon atoms, phenyl and aradical that completes a ring structure to form a heterocycle havingabout 6 to 20 carbon atoms, (ii) hard polyisocyanate residue units,wherein the polyisocyanate residue units are a polyisocyanate minus the—NCO groups, (iii) monoamine residue terminal units, wherein themonoamine residue terminal units are a amonoamine minus the —NDH groupwith D selected from hydrogen, alkyl radicals having 1 to 10 carbonatoms, phenyl and a radical that completes a ring structure to form aheterocycle having about 6 to 20 carbon atoms, and the monoamine residueterminal units have an endcapping group, and (iv) urea linkagesconnecting the isocyanate residue units, the polydiorganosiloxane amineresidue units and the monoamine residue terminal units, wherein themonoamine residue terminal units are connected through the —NDH group onthe monoamine; and (d) conveying the oligomer from the reactor.
 40. anessentially solventless process for preparing polydiorganosiloxaneoligourea segmented copolymers comprising the steps of: (a) continuouslyproviding reactants to a reactor under substantially solventlessconditions, wherein the reactants comprise (i) at least onepolyisocyanate, (ii) at least one polydiorganosiloxane diamine, and(iii) at least one non-siloxane containing endcapping agent wherein theendcapping agent has a first terminal portion reactive with anisoyanate, and a second terminal portion selected from the groupconsisting of (A) a moiety that is not reactive under moisture curing orfree radical curing conditions selected from the group consisting ofalkyl, substituted alkyl, aryl, and substituted aryl, (B) a freeradically curable end group, or (C) a moisture curable group selectedfrom the group cosisting of propyl trimethoxysilane, propyltriethoxysilane, propyl methyldimethoxysilane, propylmethyldiethoxysilane, proply dimethoxy (methylethylketoximino)silane,propyl diethoxy (methylethylketoximino)silane, propylmonomethoxydi(methylethylketoximino)silane, propylmonoethoxydi(methylethylketoximino)silane, and propyltri(methylethylketoximino)silane mixtures thereof and partialhydrolyzates thereof; (b) mixing the reactants in the reactor under thesubstantially solventless conditions; (c) allowing the reactants toreact to form a polydiorganosiloxane oligourea segmented copolymerhaving (i) soft polydiorganosiloxane amine residue units, wherein thepolydiorganosiloxane amine residue units are a polydiorganosiloxaneamine minus all —NDH groups with D selected from hydrogen, alkylradicals having 1 to 10 carbon atoms, phenyl and a radical thatcompletes a ring structure to from a hetercycle having about 6 to 20carbon atoms, (ii) hard polyisocyanate residue units, wherein thepolyisocyanate residue units are a polyisocyanate minus the —NCO groups,(iii) monoamine residue terminal units, wherein the monoamine residueterminal units are a monoamine minus the —NDH group with D selected fromhydrogen, alkyl radicals having 1 to 10 carbon atoms, phenyl and aradical that completes a ring structure to form a heterocycle havingabout 6 to 20 carbon atoms, and the monoamine residue terminal unitshave an endcapping group, and (iv) urea linkages connecting theisocyanate residue units, the polydiorganosiloxane amine residue unitsand the monoamine residue terminal units, wherein the monoamine residueterminal units are connected through the —NDH group on the monoamine;and (d) conveying the oligomer from the reactor.